Article date: 1978/12/1
PubMed ID: 215744
Journal name: The Journal of pharmacology and experimental therapeutics (ISSN: 0022-3565)
The injection of various doses of morphine, subcutaneously, or of beta-endorphin, intraventricularly, changes the turnover rate of gamma-aminobutyric acid (TRGABA) in the substantia nigra, globus pallidus and nucleus caudatus. The TRGABA decreases in N. caudatus but increases in globus pallidus and substantia nigra. These changes are dose related and can be inhibited by naltrexone. The increased TRGABA in globus pallidus elicited by these opioid receptor agonists may be associated with catalepsy since muscimol, a specific GABA receptor agonist, injected into the globus pallidus causes a dose-related catalepsy. Since this GABA receptor agonist injected into the substantia nigra fails to cause catalepsy, one can exclude that the increase in the TRGABA of substantia nigra elicited by opiate receptor agonists is operative in mediating the catalepsy elicited by opioids.
Author List: Moroni F, Cheney D L, Peralta E, Costa E
Publication Types: Journal Article
Substances mentioned in the article: Endorphins; Receptors, Opioid; Muscimol; gamma-Aminobutyric Acid; Naltrexone; Morphine;
Mesh terms: Animals; Catalepsy/chemically induced; Caudate Nucleus/drug effects; Endorphins/antagonists & inhibitors; Globus Pallidus/drug effects; Humans; Male; Morphine/antagonists & inhibitors; Muscimol/pharmacology; Naltrexone/pharmacology; Rats; Receptors, Opioid/drug effects; Substantia Nigra/drug effects; gamma-Aminobutyric Acid/metabolism;