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NIDA News Releases (Page 2)


[1997 Releases][1996 Advisories][1995 Advisories]

Index of 1997 Releases

For Immediate Release: Monday, September 29, 1997
Contact: Mona W. Brown or Sheryl Massaro: (301) 443-6245

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Preventing and Treating Heroin Use Is Focus of National Research Conference

HHS Secretary Donna E. Shalala and General Barry McCaffrey, Director of the White House Office of National Drug Control Policy, issued a challenge to over 500 attendees representing national drug abuse organizations, prevention and treatment practitioners, the media, criminal justice and law enforcement personnel, and policy makers, to use available research to respond to the changing problem of heroin use in the U.S. Speaking to over 500 participants, Secretary Shalala and General McCaffrey delivered keynote addresses at the first national research-based conference on heroin, being held September 29 and 30 at the Sheraton Washington Hotel in Washington, D.C.

The conference, Heroin Use and Addiction: A National Conference on Prevention, Treatment, and Research is sponsored by the National Institute on Drug Abuse (NIDA), National Institutes of Health. The conference provides a forum to examine all aspects of research on heroin use and an opportunity to develop strategies for using science to address the problem. Over the two days of the conference, a series of panels will address the changing trends and patterns of abuse, including the varying consequences of snorting, smoking, and injecting the drug; the biological and behavioral bases of addiction; the health and social consequences of heroin addiction, including its effect on the fetus and implications for HIV/AIDS and hepatitis B and C; and effective, science-based prevention and treatment approaches.

Other speakers include prominent researchers from around the country, Drug Enforcement Administration officials, and individuals working in the community to prevent and/or treat drug abuse and addiction and its consequences.

Dr. Alan I. Leshner, Director of NIDA, says, "It is time to take direct action to curb this growing problem of heroin use. By bringing together those working in the field and scientists who are studying heroin use and addiction, we can take a closer look at what we have learned through years of research about heroin and develop science-based approaches to address this problem."

NIDA supports more than 85 percent of the world's research on the health aspects of drug abuse and addiction and carries out a large variety of programs to disseminate research information. Further information on NIDA's research and activities can be found on the Home Page at http://www.nida.nih.gov.

For more information about the conference or to schedule an interview with Dr. Leshner or any of the speakers, call Mona Brown or Sheryl Massaro at the NIDA Press Office, 301-443-6245. NIDA will be staffing a press room at the conference.


For Immediate Release: Thursday, September 25, 1997
Contact: Mona W. Brown or Sheryl Massaro: (301) 443-6245

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New Imaging Techniques Provide Brain Map of Cocaine-Induced Euphoria and Craving

Using advanced brain imaging techniques, researchers from Harvard Medical School and Massachusetts General Hospital have identified the brain circuits activated during the distinct experiences which follow cocaine use. Their research shows that different regions of the brain are activated during a cocaine "rush," cocaine "high" and cocaine craving. These results provide a clearer and more detailed picture of cocaine's effects on the human brain, and suggest new approaches for treating aspects of cocaine use and addiction.

Using functional magnetic resonance imaging (fMRI) at Massachusetts General Hospital, Dr. Hans C. Breiter, principal investigator for the study, and his colleagues were able to measure activity in very specific regions of the brain during cocaine administration. Subjects were instructed to rate feelings of levels of the cocaine-induced "rush" and cocaine-induced craving. The fMRI produced a highly detailed map of brain activity while individuals were having these different experiences, and showed distinct patterns of activity in different parts of the brain associated with each experience.

Dr. Alan I. Leshner, Director of the National Institute on Drug Abuse (NIDA), National Institutes of Health, the Federal agency that funded the study, said, "These studies lay out in exquisite detail many of the different circuits of the brain that are activated during different behavioral experiences associated with using cocaine, and they suggest specific brain areas that might be targeted in developing new medications to either block individual aspects of cocaineŐs effects, like the rush versus the craving experiences, or as broader treatments for cocaine abuse and addiction."

Through previous studies with other techniques, scientists have gained numerous invaluable insights into how and where cocaine acts in the brain by recording nerve cell activity in the brains of laboratory animals treated with drugs. However, the animals cannot indicate what they are feeling during different states of drug-induced brain activity. Earlier techniques used in studying the effects of drugs of abuse on the human brain have been consistent with what was learned with animals, but have been unable to provide the same level of detail and specificity found in this fMRI study. "This is the first time that we have been able to show with this level of detail that the circuitry implicated in animals is actually the same as that involved in the brains of humans," Dr. Leshner added.

"An advantage of our approach [using noninvasive fMRI imaging of human subjects] is that we can actually match changes in brain activity in fine detail to the subjective sensations described by the drug user," said Dr. Breiter.

The researchers found that the cocaine rush was associated with early and short-lived increases in activity in a number of brain regions. Those regions included some areas of the cortex, the outermost area of the brain responsible for conscious thought, and some structures of the limbic system, a deeper area involved with emotions. On the other hand, cocaine craving was associated with prolonged activation of the nucleus accumbens, a region known to be involved in producing the pleasurable effects of drugs. Craving was associated also with sustained decreases in activity in some brain areas, such as the amygdala, which plays a role in aggression and other emotions.

The study on brain activity in drug-induced emotions will be published in the September 25 issue of Neuron. For more information about the study, call the NIDA Press Office at (301) 443-6245.

NIDA supports more than 85 percent of the world's research on the health aspects of drug abuse and addiction. The Institute also carries out a large variety of programs to ensure the rapid dissemination of research information and its implementation in policy and practice. Further information on NIDA research and other activities can be found on the Home Page at http://www.nida.nih.gov.


For Immediate Release: Wednesday, September 24, 1997
Contact: Mona W. Brown or Sheryl Massaro: (301) 443-6245

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Preventing and Treating Heroin Use Is Focus of National Research Conference

HHS Secretary Donna E. Shalala and General Barry McCaffrey, Director of the White House Office of National Drug Control Policy, will deliver keynote addresses at the first national research-based conference on heroin. They will issue a challenge to over 500 attendees representing national drug abuse organizations, prevention and treatment practitioners, the media, criminal justice and law enforcement personnel, and policy- makers, to use available research to respond to the changing problem of heroin use in the U.S.


Where:Sheraton Washington Hotel
Cotillion Ballroom
2660 Woodley Road, N.W.
Washington, D.C.
When:8:30 a.m. EDT
September 29, 1997
Contact:National Institute on Drug Abuse (NIDA)
Press Office
(301) 443-6245

*** NOTE: Press should contact the NIDA press office to register for the conference. A press room (Johnson Room) will be maintained throughout the conference.


For Immediate Release: Friday, July 18, 1997
Contact: Mona W. Brown or Sheryl Massaro: (301) 443-6245

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Later Criminal Behavior and Drug Use Dramatically Reduced By Drug Treatment Beginning in Prison

Comprehensive treatment of drug-addicted prison inmates, when coupled with post-release aftercare, reduces the probability of their being rearrested by 57 percent and reduces the likelihood they will return to drug use by 37 percent. In a study just published in the Journal of Drug Issues, researchers at the University of Delaware's Center for Drug and Alcohol Studies found that within 18 months after release from prison, 54 percent of untreated drug-addicted inmates were rearrested and 84 percent were back using drugs. By comparison, of the individuals receiving drug abuse treatment during their prison stay and in aftercare programs, only 23 percent had been rearrested and 53 percent had used drugs again.

"The effectiveness of this 'Delaware model' for drug treatment has tremendous implications for policy makers, incarcerated individuals and their families, and for the public," said Dr. Alan I. Leshner, director of the National Institute on Drug Abuse, National Institutes of Health, which provided funding for the study. "This study shows that treating drug-addicted offenders while they are in prison and immediately after release is an extremely effective strategy for reducing both public safety and public health costs of drug abuse and addiction."

The study was an 18-month followup of 448 individuals involved in a three-stage therapeutic community treatment model run by Correctional Medical Systems. Therapeutic communities provide long-term, residential treatment emphasizing resocialization and behavioral change toward reintegrating an individual to society. In this study, the treatment stages included a prison-based therapeutic community setting, a work release therapeutic community, and community-based aftercare, and they coincided with an individual's changing status from incarceration to work release to parole.

The individuals studied were drug-involved male and female offenders in the correctional system. They had volunteered to receive either (1) prison-based therapeutic community drug treatment only; (2) work-release therapeutic community drug treatment followed by aftercare; (3) prison-based therapeutic community treatment followed by the work-release drug treatment and aftercare; or (4) training in a work release program but no therapeutic community drug treatment.

At the 18-month followup, 77 percent of those who had received all three stages of treatment were arrest-free and 47 percent were drug-free. Of those individuals who had received only the work release and aftercare stage, 57 percent were arrest-free and 31 percent were drug-free. Of the individuals who had received no treatment, only 46 percent were arrest-free and 16 percent were drug-free at 18 months.

"The majority of individuals in prisons want to be able to live productive lives when they leave the correctional system," said Dr. James A. Inciardi, principal investigator for the study. "This treatment model can help them remain drug-free and crime-free when they return to the community, if given appropriate care during key transitions." Dr. Inciardi and his colleagues are continuing the study with followup interviews at 42 months and 54 months after release from prison.

NIDA supports more than 85 percent of the world's research on the health aspects of drug abuse and addiction and carries out a large variety of programs to disseminate research information. Further information on NIDA's research and activities can be found on the Home Page at http://www.nida.nih.gov.


For Immediate Release: Thursday, June 26, 1997
Contact: Mona W. Brown or Sheryl Massaro: (301) 443-6245

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Effects of Long-Term Marijuana Use on the Brain Shown Similar To Other Addicting Drugs

Long-term use of marijuana produces changes in the brain that are similar to those seen after long term use of other major drugs of abuse such as cocaine, heroin, and alcohol. Moreover, these changes may increase a user's vulnerability to addiction to other abusable drugs by "priming" the brain to be more easily changed by drugs in the future. This study is published in the June 27 issue of Science.

"We know that a substantial number of chronic marijuana users become addicted, and previous research with animals has shown that stopping heavy marijuana use suddenly can cause distinct withdrawal symptoms," said Dr. Alan I. Leshner, director of the National Institute on Drug Abuse, National Institutes of Health, which supported this research. "This study shows that marijuana use shares common brain changes and mechanisms with other drugs of abuse."

This study was conducted by scientists in the United States and Spain to discover whether CRF (corticotropin-releasing factor), a brain chemical which increases during emotional times and periods of stress, plays a role in dependence on cannabis, the plant from which marijuana and hashish are derived. Earlier studies have suggested that CRF plays a role in the neurobiological and behavioral effects of withdrawal from addiction to cocaine, alcohol, and opiates, and possibly a role in drug dependence in general.

Rats were injected with HU-210, a potent substance that mimics the effects of marijuana. An analysis of the rats' brains showed that one injection of HU-210 reduced the release of CRF in the amygdala, a key brain structure involved in emotions.

After 14 days of HU-210 treatment, the researchers induced drug withdrawal by injecting rats with the antagonist SR 141716A, a substance that blocks many effects of marijuana. The marijuana-treated rats showed many withdrawal symptoms after marijuana antagonist injection. Moreover, these rats showed an increased release of CRF at the same time they demonstrated dramatic behavioral withdrawal symptoms. Importantly, the specific brain areas that were activated during cannabinoid withdrawal are quite active during withdrawal from other drugs of abuse and play a key role in stress responses in general.

"These results provide evidence that long-term exposure to cannabinoids leads to changes in the brain that activate stress-like responses during cannabinoid withdrawal," said Dr. Friedbert Weiss, one of the study's investigators at the Scripps Research Institute in La Jolla, CA. "These changes in CRF functioning in the brain are similar to those seen during withdrawal from alcohol, cocaine, and opiates, as well as during exposure to environmental stressors," he added.

Dr. George Koob, also from Scripps Research Institute, observed that "the finding from this and other studies that long-term exposure to cannabinoids can produce changes in the brain that resemble those associated with other major drugs of abuse suggests that addiction to one drug may make a person more vulnerable to abuse and addiction to other drugs. Cannabinoid abuse, by activating CRF mechanisms, may lead to a subtle disruption of brain processes that are then 'primed' for further and easier disruption by other drugs of abuse."

The study was supported in the United States by the National Institute on Drug Abuse and the National Institute of Diabetes, Digestive and Kidney Diseases, both parts of the National Institutes of Health, and in Spain, by the Comisión Interministerial de Ciencia y Tecnología, and Comunidad Autónoma de Madrid.

NIDA supports more than 85 percent of the world's research on the health aspects of drug abuse and addiction and carries out a large variety of programs to disseminate research information. Further information on NIDA's research and activities can be found on the Home Page at http://www.nida.nih.gov.


For Immediate Release: Tuesday, June 24, 1997
Contact: Mona W. Brown or Sheryl Massaro: (301) 443-6245

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Medication for Treating Heroin Dependence Proven Safe and Very Effective If Used at High Enough Doses

Heroin-dependent individuals reduced their use of heroin by up to 90 percent using the treatment medication LAAM (levomethadyl acetate hydrochloride), according to research published in the June 25 issue of the Journal of the American Medical Association (JAMA). In this first clinical trial comparing different LAAM doses in the treatment of opiate addiction, researchers found that heroin use was reduced for individuals taking a regimen of low, medium, or high doses of LAAM, with effectiveness increasing substantially at the highest dose. This suggests treatment programs need to get patients to the most effective dosage levels as quickly as possible.

This was also the first double-blind clinical trial to include women. Women and men responded equally well to LAAM, and high doses were found to be safe for both male and female heroin addicts. LAAM was approved by the Food and Drug Administration as an opiate treatment medication in 1993 and was, at that time, the first new drug treatment medication approved in more than two decades. LAAM's main advantage over methadone, widely used in heroin treatment, is that its effects last long enough so that it need be taken only three times per week. Methadone needs to be taken daily, requiring either a daily trip to a clinic or take-home dosages.

"This study reinforces the fact that heroin addiction can be treated effectively," said Dr. Alan I. Leshner, director of the National Institute on Drug Abuse, National Institutes of Health, which supported this research. "When higher doses of LAAM are used in combination with other drug abuse treatment methods, such as behavioral therapies and psychosocial care, we may see even more positive outcomes for persons who are opioid dependent."

The 17-week study was conducted with 180 heroin-dependent volunteers (70 females, 110 males) by researchers at the Behavioral Pharmacology Research Unit of the Johns Hopkins University Bayview Medical Center in Baltimore, Md. None of the volunteers was concurrently in a treatment program. Upon admission to the study, patients were randomly assigned to a high-, medium-, or low-dose LAAM therapy group.

LAAM reduced heroin use in a dose-related pattern. Before assignment to the high-dose group, patients reported using heroin an average of 29 of the past 30 days. After 16 weeks of LAAM treatment, these same patients reported using heroin an average of 2.5 of the past 30 days, a reduction of nearly 90 percent. Patients assigned to the medium-dose treatment group reported using heroin an average of 4.1 days and those in the low-dose group an average of 6.3 days. These self-report findings were corroborated through urine testing. In addition, patients taking high-doses of LAAM were twice as likely to achieve four weeks of full abstinence compared to patients taking lower doses of LAAM.

Both men and women showed the same general positive relationship between dose level and treatment effectiveness. However, six of the eight women who left treatment reported feeling overmedicated. The researchers suggest that adjusting LAAM doses for weight variation may decrease the overmedication and promote patient retention.

"This study is important because the effectiveness of the most widely used heroin-dependence medication, methadone, has not been fully realized because of a lack of information regarding effective doses," said Dr. George Bigelow, director of the Pharmacology Research Unit at Johns Hopkins University. "The completion of this dose-comparison study of LAAM will allow clinicians to base their dosing decisions on empirical data and may help to increase LAAM's therapeutic effectiveness."

This research was funded by the National Institute on Drug Abuse, NIH, whose Medications Development Division has coordinated federal efforts to develop medications to augment behavioral and psychotherapies also used in comprehensive drug treatment programs.

NIDA supports more than 85 percent of the world's research on the health aspects of drug abuse and addiction and carries out a large variety of programs to disseminate research information.


For Immediate Release: Monday, June 23, 1997
Contact: Mona W. Brown or Sheryl Massaro: (301) 443-6245

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Researchers Meet to Discuss Emerging Drug Trends in U.S. Metropolitan Areas and Internationally

Current and emerging patterns and trends in drug abuse will be discussed at the 42nd meeting of the Community Epidemiology Work Group (CEWG) to be held June 24-27 at the Madison Hotel in Washington, D.C. The CEWG is a network of researchers and public health officials from 20 major U.S. metropolitan areas who meet semiannually to share their regionŐs current patterns and trends of drug abuse. This meeting will also include international findings from members of the International Epidemiology Work Group on Drug Abuse (IEWG). The meeting will be held under the auspices of the National Institute on Drug Abuse, National Institutes of Health.

"For 21 years, the CEWG has given the country frontline reports on emerging drug use trends in the United States," notes Dr. Alan I. Leshner, director of the National Institute on Drug Abuse. "Advance knowledge of new forms of drug use, such as marijuana 'blunts' and reports of localized drug use problems from these important urban areas are invaluable to our understanding of drug use nationwide."

The CEWG model, which uses information from regional public health agencies, medical and treatment facilities, criminal justice and correctional offices, law enforcement agencies, drug use surveys, and other sources, has been adapted successfully at local, State, and international levels.

The report from the previous CEWG meeting, held in December 1996, indicated rises in marijuana use based on increases in marijuana-related emergency room mentions, drug treatment admissions, and other data presented. There was also a rise in new heroin users snorting the drug rather than injecting the drug. Details of these and other findings are in the Advance Report of the December 1996 Meeting of the Community Epidemiology Work Group.

The CEWG is a network of researchers from Atlanta, Boston, Chicago, Denver, Detroit, Honolulu, Los Angeles, Miami, Minneapolis/St. Paul, Newark, New Orleans, New York, Philadelphia, Phoenix, San Diego, San Francisco, St. Louis, Seattle, Washington, D.C., and from the State of Texas. Specific information sources include the treatment data from State substance abuse agencies; the Substance Abuse and Mental Health Services AdministrationŐs Drug Abuse Warning Network (DAWN); the National Institute of JusticeŐs Drug Use Forecasting (DUF) System; and seizure, price, purity, prescription/distribution, and arrest data from the Drug Enforcement Administration and State and local law enforcement agencies. CEWG meetings are held in winter and summer each year.

The international component of this meeting, on June 26 and 27, will include presentations from researchers and discussions among health officials and academicians representing the United Nations International Drug Control Program, the Council of Europe and the European Union, the Organization of American States, and the World Health Organization; and from selected countries, including Australian, Canada, Malaysia, Mexico, South Africa, and Spain.

Dr. Leshner and Mr. Jeremy Travis, Director of the National Institute of Justice, will co-chair an international panel during the meeting focusing on the effective use of epidemiologic data in developing a research agenda, public health policy, and delivery of treatment and prevention services.

The press are invited to attend the meeting from June 25-27. To register or arrange interviews, please call the NIDA press office at (301) 443-6245.

NIDA supports more than 85 percent of the world's research on the health aspects of drug abuse and addiction and carries out a large variety of programs to disseminate research information.


For Immediate Release: Wednesday, April 30, 1997
Contact: Mona W. Brown or Sheryl Massaro: (301) 443-6245

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Chicago Area Town Meeting and School Event to Promote Understanding and Dispel Myths About Drug Abuse and Addiction

The National Institute on Drug Abuse, National Institutes of Health (NIDA), will hold a community Town Meeting in Chicago on May 30, 1997 from 8:30 a.m. to 5:00 p.m. at the Hyatt Regency Chicago. NIDA Director Alan I. Leshner, Ph.D., will convene the Town Meeting on Understanding Drug Abuse and Addiction: Myths versus Reality. Scientists and community leaders will discuss the problem of drug abuse in the State of Illinois and in the Chicago area, and consider how the results of research can be used to improve the response to the problem.

On May 29 from 7:00 p.m. to 9:00 p.m., Dr. Leshner will join parents, students, teachers, and community leaders at Glenbrook South High School in Glenview, Illinois for a discussion on Drug Abuse and Our Youth. The focus will be on the latest research about the consequences, prevention, and treatment of drug abuse and addiction among today's young people. Citizens concerned about the problems of drug abuse are invited to participate.

"We know from research that drug abuse is a preventable behavior and drug addiction is a treatable illness or disease. One of NIDA's most important goals is to expand our efforts to translate research findings, especially those about the actions and effects of drugs on the brain, to help the public better understand the nature of addiction and the most effective strategies for its prevention and treatment," Dr. Leshner said.

The Chicago Town Meeting is designed as a dialog between scientists and local participants to educate the public about drug abuse and how to use science to shape local and State policy. The meeting will include scientists, civic leaders, policymakers, public officials, and drug abuse prevention and treatment professionals. Topics include advances from research on drug abuse and the brain, and current research in drug abuse prevention and treatment. Key drug abuse researchers will discuss local trends and patterns of abuse, community attitudes toward alcohol and drug abuse, and effective strategies for prevention. The general public is invited and encouraged to participate in the discussion.

"The Town Meeting is also a forum for local participants to advise NIDA on the kinds of research-based information needed at the State and local levels. In this way, we can make sure the research NIDA supports is both useful and used," Dr. Leshner added.

The Town Meeting is cosponsored by the Office of Substance Abuse Policy - City of Chicago; the Office of the Lieutenant Governor/Partnership for a Drug-Free Illinois; the Illinois Department of Alcoholism and Substance Abuse; and the Illinois Society of Addiction Medicine. A $25 registration fee covers the cost of the May 30 Town Meeting and lunch. Registration information may be obtained from the Mayor's Office of Substance Abuse Policy at 312-747-2606. For information on the Glenbrook South High School event, please contact Carol Joy Cunningham at 847-940-0202.

Members of the press who want to attend the Town Meeting or the Glenbrook South High School event, or arrange interviews, should contact the NIDA Press Office at 301-443-6245.

Dr. Leshner and other speakers will be available for interviews before and during both meetings.

NIDA supports more than 85 percent of the world's research on the health aspects of drug abuse and addiction. The Institute also carries out a large variety of programs to ensure the rapid dissemination of research information and its implementation in policy and practice.

The Chicago Town Meeting is the fifth in a series of NIDA-sponsored meetings in selected cities throughout the Nation to refocus the public's perception of drug abuse and addiction to one based in scientific research.


For Immediate Release: Thursday, April 24, 1997
Contact: Mona W. Brown or Sheryl Massaro: (301) 443-6245

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Scientists Identify Brain Mechanisms of Cocaine's Euphoric Effects

For the first time, researchers have observed in human cocaine abusers some of the ways by which cocaine produces its pleasurable effects as they are occurring. Researchers at the Brookhaven National Laboratory in Upton, NY, State University of New York at Stony Brook, and Columbia University have found a significant relationship between the intensity and duration of the "high" induced by cocaine and the degree to which the drug blocks one of the major mechanisms to control the amount of dopamine in the brain. There is a clear relationship between the degree to by which cocaine blocks the dopamine transporter and the cocaine abuser's experience of euphoric feelings. The results of this study using the brain imaging techniques of positron emission tomography (PET) will appear in the April 24, issue of Nature.

Until now, scientists have relied heavily on animal models to determine how cocaine produces its effects and to identify which sites in the brain are primarily involved. Those studies have suggested that cocaine works in large part by occupying or blocking dopamine transporter (DAT) sites, thereby preventing reuptake of dopamine by the brain cells that release it, which then allows higher concentrations of dopamine to remain available in the brain longer than normal. It is this abnormally long presence of dopamine in the brain that is believed to cause the high and other effects associated with cocaine use.

To study the relationship between subjective effects of cocaine and its activity in the brain of humans, Dr. Nora Volkow and colleagues gave injections of cocaine to 17 volunteers who were current cocaine users. Using PET scans, they produced images of the volunteers' brains showing the concentrations of cocaine occupying DAT sites. They found that doses of cocaine commonly abused by humans blocked about 60 to 77 percent of the cocaine users' DAT sites. The researchers also asked the volunteers to describe the effects they felt from the drug as it was being administered and their brain activity monitored.

By analyzing the PET images together with the volunteers' subjective reports on the drug's effects, the researchers were able to document a significant relationship between the intensity and duration of the high induced by the cocaine and the concentration of the drug at DAT sites seen in the PET scans. In order for the subjects to perceive cocaine's effects, at least 47 percent of the DAT sites had to be blocked by cocaine.

"To our knowledge, this is the first demonstration in humans that the doses often used by cocaine abusers lead to the significant blockade of DAT sites and that this blockade is actually associated with the subjective effects of cocaine," said Dr. Nora D. Volkow, Chair of the Medical Department and Director of Nuclear Medicine at the Brookhaven National Laboratory. "These results clarify the role of the DAT blockade as a crucial mechanism in the reinforcing properties of cocaine in humans," she concluded.

Dr. Alan I. Leshner, Director of the National Institute on Drug Abuse (NIDA), which funded this study in conjunction with the Department of Energy, said, "This study demonstrates the potential of human neuroscience research as it allows us to look into the brains of people experiencing various aspects of cocaine addiction. Researchers can now see specifically where cocaine acts in the brain and can then target efforts to block those effects and treat their addiction."

In another study published in the same issue of Nature, Dr. Volkow and colleagues compared the functioning of the dopamine system in the brains of chronic cocaine users with that in non-users. Methylphenidate, a stimulant similar to cocaine that increases dopamine responsiveness in the brain, was administered to both the users and non-users. Using the PET technology, researchers obtained brain images that contrasted how the dopamine systems in the two groups responded to the methylphenidate.

They found that, compared to the non-users, the cocaine-dependent group showed reduced dopamine responses to the drug in the striatum, a region of the brain linked to motivation control and reward. At the same time, they found an abnormal increase in the level of dopamine response in the thalamus, a region of the brain that communicates sensory information. This enhanced response in the thalamus, which also was associated with experiences of intense cocaine cravings among those who were addicted to cocaine, was not observed in the control group.

In explaining the significance of this study, Dr. Volkow said, "This research suggests that dopamine pathways in the thalamus as well as in the striatum are critically involved in cocaine addiction. More research is needed to determine just how drug-related changes in these areas of the brain may affect drug cravings and compulsive drug use by cocaine addicts."

NIDA supports more than 85 percent of the world's research on the health

aspects of drug abuse and addiction and carries out a large variety of programs to disseminate research information.


For Immediate Release: Tuesday, April 22, 1997
Contact: Mona W. Brown or Sheryl Massaro: (301) 443-6245

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Role Found for Natural Body Opioids in Reproduction and Resistance to Infection

Scientists have discovered that the body's natural opioid system is far more important and has broader effects than ever thought. In addition to being essential to responses to pain and the euphoria from drugs such as morphine, codeine, and heroin, the mu opioid receptor, the cellular target of these drugs, also appears to be involved in regulating the immune and reproductive systems.

Researchers at the Indiana University School of Medicine have shown that, in addition to failing to respond to narcotic drugs, like morphine, mice missing the gene for the mu opioid receptor also show reduced sexual and reproductive function and altered immune systems.

Dr. Lei Yu and his colleagues showed that when the functioning of the mu opioid receptor is disabled by a technique called "knocking out" the gene responsible for its production, mice not only fail to respond to the pain-relieving properties of morphine, but their sexual behavior, their reproductive functioning, and their immune systems are also modified. Mice lacking mu opioid receptors experienced increased production of blood progenitor cells, including white blood cells which defend the body against infection, in their bone marrow and spleen. In addition, male mice lacking mu opioid receptors engaged in less mating activity; had fewer, less active sperm; and fathered smaller litters than did male mice with intact mu opioid receptors.

It has been known since the 1970s that the body has a natural opioid system that acts much in the same way as opiate drugs like heroin and morphine. Not only are there receptors throughout the body that respond to opiate substances, but the body produces natural opioids that are released during strenuous exercise and in response to stress or pain. These natural substances are involved in the body's control of pain reactions and play a role in many other behaviors, like the experience of pleasure.

Although the effects of the mu opioid receptor on perceiving pain or pleasure may seem unrelated to the immune and reproductive systems, Dr. Yu suggests that, "These results indicate that the mu opiod receptor is involved in a range of diverse biological processes."

Dr. Alan I. Leshner, Director of the National Institute on Drug Abuse, which supported this study, said, "These observations in the mouse model track very well with anecdotal accounts that humans using heroin and morphine experience both reduced immune function and reduced sex drive. Not only do opiates affect mood states and produce addiction, but it also appears that their effects on natural opioid receptors lead to changes in their capacities to reproduce and to resist infection and disease. The findings emphasize the very broad implications of narcotic drug use on both the health of an individual and the public."

Dr. Leshner added, "This study builds on Dr. Yu's earlier work, where he and his colleagues first broke the genetic code for the mu opiod receptor. They now have demonstrated its importance in many different biological arenas. Understanding both the structure and, now, the broader range of functions of this receptor will aid tremendously in our efforts to develop medications to address the problem of opiate use and addiction and their resulting health consequences."

The study was published in the April 21, 1997, issue of the Journal of Experimental Medicine.

NIDA supports more than 85 percent of the world's research on the health aspects of drug abuse and addiction. The Institute also carries out a large variety of programs to ensure the rapid dissemination of research information and its implementation in policy and practice.


For Immediate Release: Friday, April 4, 1997
Contact: Mona W. Brown or Sheryl Massaro: (301) 443-6245

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Genetic Basis Indicated for Abuse of Marijuana

Scientists have found that whether an individual has positive or negative sensations after smoking marijuana is heavily influenced by heredity, according to a study published in the April 1997 issue of the international medical journal, Addiction.

A study funded by the National Institute on Drug Abuse (NIDA), National Institutes of Health, demonstrated that identical male twins were more likely than non-identical male twins to report similar responses to marijuana use, indicating a genetic basis for their sensations. Identical twins share all of their genes, and fraternal twins share about half.

NIDA Director Dr. Alan I. Leshner said, "The finding that genetic factors contribute to how an individual feels after using marijuana opens new avenues for prevention and treatment research. And it further emphasizes that drug use and addiction are not simply social problems, but are health issues affected by an individual's biological state."

Dr. Michael Lyons, Dr. Ming Tsuang, and their colleagues at the Harvard Medical School in Boston, compared identical and fraternal twins on a series of questions in a detailed confidential interview of how "pleasant" or "unpleasant" they felt after smoking marijuana. The identical twins answered similarly while the fraternal twins did not. The results indicate that genes have a significant influence on individual pleasant or unpleasant responses to the effects of marijuana.

Environmental factors such as the availability of marijuana, expectations about how the drug would affect them, the influence of friends and social contacts, and other factors that would be different even for identical twins were also found to have an important effect; however, it was also discovered that the twins' shared or family environment before age 18 had no detectable influence on their response to marijuana.

Taking the environmental and genetic influences together, these results suggest that while exposure to marijuana by factors such as social contacts are important, there are individual differences, perhaps in the brain's reward system, associated with genetic factors that influence whether one will continue using marijuana. Environmental factors may lead to an individual's experimenting with a drug, according to Dr. Tsuang, but heredity appears to hold the key to whether or not an individual will continue to use or abuse the drug.

More than 8,000 male twins, drawn from the Vietnam Era Twin Registry, participated in the study. Of these, 352 pairs of identical twins and 255 pairs of fraternal twins each reported having used marijuana more than 5 times. These individuals were asked if they had experienced each of 23 possible reactions, ranging from confused or paranoid ("negative" responses) to relaxed or mellow ("positive" responses) after marijuana use. Not surprisingly, individuals who perceived marijuana use as pleasurable tended to use it more frequently and those who found the experience unpleasant tended to use it less often. The experienced reactions to marijuana use were more similar for identical twins than fraternal twins.

"This study confirms our hypothesis that genes map an individual's physiology in ways that determine how the individual will feel when using marijuana," said Dr. Lyons. The specific gene or genes involved could not be identified from this study, but it is speculated they are those involved in the brain's reward system.

These physiological differences coupled with the observation that individuals who find pleasure in using marijuana are more likely to use it repeatedly lead to the conclusion that heredity plays a significant role in determining susceptibility to continuing marijuana abuse. The authors postulate that their finding might apply also to use of other substances as well, such as alcohol and cocaine.

NIDA supports more than 85 percent of the world's research on the health aspects of drug abuse and addiction. The Institute also carries out a large variety of programs to ensure the rapid dissemination of research information and its implementation in policy and practice. Further information on NIDA research and other activities can be found on the Home Page at http://www.nida.nih.gov.


For Immediate Release: Thursday, March 6, 1997
Contact: Mona W. Brown or Sheryl Massaro: (301) 443-6245

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New Research-Based Guide Now Available To Help Prevent Teen Drug Use

Online Version AvailableP

HHS' National Institute on Drug Abuse today released the first research-based guide to preventing young people from using drugs. A first printing of more than 100,000 copies of the new guide will be distributed to schools and community groups nationwide in the coming months.

"Over the past 20 years, HHS and the National Institute on Drug Abuse have supported a rigorous research program to determine what really works to help prevent drug abuse among our youth," said HHS Secretary Donna E. Shalala. "Today we have assembled what we know, and we want to share it with families and schools in every community across America."

The new guide, "Preventing Drug Use Among Children and Adolescents: A Research-Based Guide," is organized around 14 prevention principles distilled from research on effective prevention techniques, and notes that every dollar spent for effective prevention programs can save $4 to $5 in the costs of treatment and counseling.

The principles call for targeting all forms of drug abuse, including alcohol and tobacco as well as illegal drugs. They also call for prevention efforts that strengthen anti-drug norms in schools and communities and that teach skills for resisting drugs when offered. And they call for enhancing "protective factors" like family bonds and good school performance, as well as addressing risk factors for drug abuse.

The Guide also includes a checklist for communities to use in evaluating their own anti-drug efforts.

Speaking at the 20th annual PRIDE conference in Atlanta, GA, where he announced the availability of the new booklet, Dr. Alan I. Leshner, director of NIDA said, "With the growing problem of adolescent drug use, there is a need to make better use of scientific knowledge to produce more enduring and effective drug prevention approaches. While each community should choose a drug prevention program that's right for local circumstances, we hope these guidelines will help them identify and incorporate the most critical proven elements."

Designed in an easy to read, easy to apply format, "Preventing Drug Use Among Children and Adolescents" summarizes knowledge gleaned from over 20 years of research and suggests how to apply it to successfully prevent drug use among young people. The 14 basic principles needed for prevention programs to be effective include:

  • Prevention programs should be designed to enhance "protective factors" and move toward reversing or reducing known "risk factors."

  • Prevention programs should target all forms of drug abuse, including the use of tobacco, alcohol, marijuana, and inhalants.

  • Prevention programs should include skills to resist drugs when offered, strengthen personal commitments against drug use, and increase social competency (e.g., in communications, peer relationships, self-efficacy, and assertiveness), in conjunction with reinforcement of attitudes against drug use.

  • Prevention programs for adolescents should include interactive methods, such as peer discussion groups, rather than didactic teaching techniques alone.

  • Prevention programs should include a parents' or caregivers' component that reinforces what the children are learning - such as facts about drugs and their harmful effects - and that opens opportunities for family discussions about use of legal and illegal substances and family policies about their use.

  • Prevention programs should be long-term, over the school career with repeat interventions to reinforce the original prevention goals. For example, school-based efforts directed at elementary and middle school students should include booster sessions to help with critical transitions from middle to high school.

  • Family-focused prevention efforts have a greater impact than strategies that focus on parents only or children only.

  • Community programs that include media campaigns and policy changes, such as new regulations that restrict access to alcohol, tobacco, or other drugs, are more effective when they are accompanied by school and family interventions.

  • Community programs need to strengthen norms against drug use in all drug abuse prevention settings, including the family, the school, and the community.

  • Schools offer opportunities to reach all populations and also serve as important settings for specific subpopulations at risk for drug abuse, such as children with behavior problems or learning disabilities and those who are potential dropouts.

  • Prevention programming should be adapted to address the specific nature of the drug abuse problem in the local community.

  • The higher the level of risk of the target population, the more intensive the prevention effort must be and the earlier it must begin.

  • Prevention programs should be age-specific, developmentally appropriate, and culturally sensitive.

  • Effective prevention programs are cost-effective. For every dollar spent on drug use prevention, communities can save 4 to 5 dollars in costs for drug abuse treatment and counseling.

Presented in a question and answer format, the guide addresses important issues regarding prevention, including, the origins and pathways of drug abuse and how these concepts are used to develop prevention intervention strategies. The guide summarizes the results of research related to the prevention of drug abuse and explains the importance of this research for teachers, parents or others concerned about preventing drug use among youth. The guide also answers questions commonly asked by community leaders and prevention practitioners in a way that they can use these research findings to design and implement programs to address drug abuse problems at the local level.

The guide provides 10 examples of programs that have been scientifically studied and have been found to be effective in preventing youth drug use. The programs are categorized as universal (reaching the general population), selective (targeting groups at risk or subsets of the general population), or indicated (designed for people already experimenting with drugs or exhibiting risk-related behaviors).

Also included in the guide is an extensive list of resources to get supporting information on drug abuse prevention or to speak directly with scientists who have developed and/or evaluated effective prevention programs.

NIDA supports over 85% of the world's research on the health aspects of drug abuse and addiction. The Institute also carries out a large variety of programs to ensure the rapid dissemination of research information and its implementation in policy and practice.

Additional information on prevention and other research activities of NIDA can be found on the Home Page at http://www.nida.nih.gov.

Note: HHS press releases are available on the World Wide Web at: http://www.dhhs.gov/



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