NCJ Number
57833
Date Published
1979
Length
8 pages
Annotation
FOCUSING ON BASIC RESEARCH ADVANCES, THIS ARTICLE EXAMINES THE COMPLEXITIES OF OPIATE AND ALCOHOL ABUSE, AS WELL AS THE EFFECTS OF NICOTINE AND BENZODIASEPHINE.
Abstract
PHARMACOLOGIC ACTIONS OF MORPHINE AND RELATED OPIATES ARE COMPLEX. THESE SUBSTANCES ARE THE MOST EFFECTIVE PAIN KILLERS KNOWN, AND CAN GREATLY ALTER EMOTIONAL RESPONSES TO PAIN AND STRESS. IT IS NOW KNOWN THAT THERE ARE HIGHLY SPECIFIC RECEPTORS ON NERVE CELLS WHICH ACCEPT ONLY THE PARTICULAR SHAPE OF THE OPIATE MOLECULE. THE TERM ENDOMORPHIN IS USED IN A GENERIC SENSE TO MEAN ANY MORPHINE-LIKE PEPTIDE; ENKEPHALIN REFERS TO SMALL BRAIN PEPTIDES. ENKEPHALIN-CONTAINING NEURONS AND OPIATE RECEPTORS ARE DEPLOYED TOGETHER THROUGHOUT THE NERVOUS SYSTEM. ENKEPHALINS ARE DESTROYED RAPIDLY IN BRAIN TISSUE; THEY HAVE THE CHARACTERISTICS OF NEUROTRANSMITTERS WHICH ACT QUICKLY, AND ARE THEN BROKEN DOWN. ACTIONS OF ENDORPHINS AT THE OPIATE RECEPTORS ARE ALSO UNDERSTOOD; THEY ARE INHIBITORS OF NERVE ACTIVITY THROUGH DIMINISHING THE RELEASE OF NEUROTRANSMITTERS. EMPLOYING KNOWLEDGE OF THIS PROCESS, NALOXONE IS USED EFFECTIVELY TO COMBAT OPIATE EFFECTS BY OCCUPYING THE OPIATE RECEPTORS WITHOUT ACTIVATING THEM; IT CAN SUCCESSFULLY REPLACE HEROIN AND MORPHINE FROM THE RECEPTORS LOCATED IN THE BRAIN OR SPINAL CORD. A BASIS FOR SPECULATION ABOUT ENDORPHIN DEFICIENCY IN OPIATE ADDICTION IS THE FACT THAT GENETIC DEFECTS CAN OCCUR IN THE PRODUCTION OF PEPTIDES; SUCH AN INBORN DEFECT IN ENDORPHIN PRODUCTION MIGHT PREDISPOSE SOME INDIVIDUALS TO BECOME HEROIN ADDICTS, WHILE OTHERS MIGHT BE ABLE TO TRY THE SUBSTANCE WITHOUT BECOMING ADDICTED. IN ALCOHOL ABUSE, THE MECHANISM THAT CAUSES INTOXICATION AND DEPENDENCE FROM A NEURO-CHEMICAL STANDPOINT IS UNKNOWN. SINCE THE ETHYL ALCOHOL MOLECULE IS SMALL, IT APPEARS UNLIKELY THAT THERE ARE SPECIFIC ALCOHOL RECEPTORS; IT IS BELIEVED THAT ALCOHOL DISSOLVES IN THE NERVE CELL MEMBRANES, PRODUCING RESULTANT PHARMACOLOGICAL EFFECTS. ALTHOUGH TOBACCO ADDICTION IS COSTLY IN TERM OF DEATH AND ILLNESS, IT IS STILL NOT KNOWN WHETHER TOBACCO ADDICTION IS REALLY A PHARMACOLOGIC ADDICTION TO NICOTINE OR WHETHER IT IS BASED UPON SOCIAL CUSTOM OR ORAL GRATIFICATION FACTORS; IT IS HOPED THAT EVENTUALLY PHYSICAL IDENTIFICATION OF NICOTINE RECEPTORS WITHIN THE BRAIN WILL BE POSSIBLE. FINALLY, WITH REGARD TO THE BENZODIAZEPINES (DRUGS WITH ANTIANXIETY PROPERTIES SUCH AS VALIUM) IT IS KNOWN THAT THESE DRUGS ALSO WORK ON THE BRAIN RECEPTOR SYSTEM, ALTHOUGH NONE OF THE KNOWN NEUROTRANSMITTERS COMBINES WITH THEM. AS WITH OPIATE RECEPTORS, BENZODIAZEPINE RECEPTORS ARE FOUND IN ALL VERTEBRATES, ONLY IN NERVOUS TISSUE. A SELECTED BIBLIOGRAPHY IS INCLUDED. (LWM)