Sparked by recent advances in opiate studies and other basic research, drug abuse researchers are excited about the promise of what may lie ahead. I share that excitement because I believe, as they do, that we may be on the brink of making important new discoveries to help us more effectively address the problems of drug abuse and addiction.
Since I became NIDA's director last February, I have immersed myself in each aspect of NIDA's research portfolio. I have been tremendously impressed myself with the extent of drug abuse research advances made by NIDA-supported investigators and intramural scientists. However, at the same time, I have found that few people besides the researchers themselves know about the depth and breadth of these findings. So far as I can tell, it is largely scientists alone who fully appreciate the potential for new drug abuse discoveries.
The public's widely recognized concerns about drug abuse and related crime issues are leading to critical policy deliberations involving everything from law enforcement and prison sentencing to foreign relations. Unfortunately, the decisions that result are often made without full consideration of the wealth of current research advances that have improved our fundamental understanding of drug abuse. Research findings are not reaching those who need to understand and act on them.
I think that it is time to correct this situation. Given the importance of the problems we are addressing- drug abuse and addiction-NIDA must be more than a purely scientific institute. Besides conducting critical research, we must both provide information necessary for making policy decisions and give guidance to treatment and prevention efforts. We need to make sure that the information we generate is disseminated quickly and effectively to policymakers, treatment and prevention practitioners, and the general public. We must strive to make sure our research findings both understandable and relevant to treatment and prevention practitioners so that they better comprehend their patients' problems and why and how the prevention and treatment approaches they use work.
In the months and years ahead, NIDA will be exploring new avenues to broaden the dissemination of research findings and to continue to improve drug abuse prevention and treatment practices and policies. We also will intensify our efforts to use scientific knowledge more effectively to educate the public about the real nature of drug abuse and addiction. The public, too, should share the hopes of our researchers.
What are some of the reasons for these hopes?
It was the groundbreaking discovery of the opioid receptor in 1973 that launched the modern era of drug abuse studies. Scientists demonstrated that the opioid receptor is the molecular site in the brain where opiates begin their euphoric and addictive action.The receptor breakthrough was soon followed by the discovery of the endogenous opioid peptides-the "brain's own morphine"-which bind to opioid receptors to reduce pain and stress. These two key opiate research discoveries inspired a generation of researchers.From its founding 20 years ago, NIDA's record of achievement based on opiate research has been lengthy and impressive and has included these contributions:
- Researchers expanded the findings about opioid receptors and the endogenous opioid peptides to apply to the fundamental concept of how all drugs and neuroactive compounds interact with receptors. These discoveries have led to the development of treatments for opiate abuse, potentially safer pain-relieving drugs, and corollary advances in studies of other drugs of abuse. In addition, these research advances continue to have far-reaching implications for biomedical investigations in numerous scientific fields outside of drug abuse.
- NIDA research that began with the opiate studies produced a neurobehavioral model to interpret drug-seeking and drug-abusing behavior that is associated with the use of many drugs of abuse.
- The cloning of the genes for three types of opioid receptors by NIDA researchers and other over the last 2 years has generated great scientific interest. The cloning, which revealed the key to the genetic structure of the receptors, opens new possibilities for exploring how receptors interact with drugs of abuse.
- Research findings about the opiates have revolutionized thinking about brain function at both the cellular and molecular levels. Opiate studies helped give investigators more sophisticated ways to study how drugs work both inside and outside brain cells and how they influence the action of neurotransmitters, chemical messengers that send signals from one nerve cell to another. Some NIDA-funded researchers are now using three-dimensional computer modeling techniques to explore how the molecules of receptors, drugs and naturally produced brain compounds fit together to influence the central nervous system. Other investigators are using neuroimaging techniques to actually "see" the changes in the physiology of the brain caused by drug abuse.
- Investigators have long suspected that cocaine addiction involves mechanisms and brain pathways that appear to be mediated by the neurotransmitter dopamine. In 1987, staff investigators in NIDA's intramural research program identified the brain receptor at which cocaine's addictive action is thought to be centered. This receptor is located on a transporter that recycles dopamine and is believed to be the key to producing cocaine's high. Cloning of the gene for the dopamine transporter by NIDA intramural researchers and extramural scientists in 1991 revealed the structure of this rapidly led to a new understanding of how cocaine works in the brain. NIDA's Medications Development Division is building on these findings in its search for a medication to block cocaine's action.
- NIDA's drug abuse research also has led down some unexpected pathways outside the field of drug abuse:
- Researchers are examining the role of endogenous opioid peptides in sudden infant death syndrome.
- In the field of learning and memory, endogenous opioids called dynorphins have been found to function as a sort of transmitter blocker, capable of long-term inhibition of functions of hippocampus, the brain's seat of memory.
- Some critical recent studies to combat AIDS- experiments to block receptors on T cells to prevent HIV infection-can be traced back to the discovery of the opioid receptor.
While this is by no means an exhaustive list of NIDA's basic research accomplishments, I believe it provides a clear understanding of why drug abuse researchers are excited and hopeful.
Dr. Huda Akil of the University of Michigan, on of NIDA's original grantees, has been closely involved with advances in opiate research since the 1970s. In tracing the history of opiate research at NIDA's June conference on progress in neuroscience research, Dr. Akil spoke of the enthusiasm and hope now prevalent among veteran researchers as they employ the latest technologies and knowledge in studying drug abuse.
"This is just the beginning" in the scientific quest to fully understand how the brain works and to pinpoint the cellular and molecular mechanisms of drug addiction, she said.
We need to spread the word so that the public, too, will share researchers' feelings of excitement and hope about finding better ways to prevent and treat drug abuse.