Article date: 1989/7/1
PubMed ID: 2548112
Journal name: Neuropharmacology (ISSN: 0028-3908)
Submaximal contractions of the isolated guinea-pig ileum by the GABAA receptor agonist muscimol were enhanced by about 30% in the presence of 1-100 pM cortisol. At 10 nM cortisol, the enhancement was much less and, at 1 microM, the responses to muscimol were reduced by about 50%. Corticosterone had similar effects but it was 100-1000 times less potent. In contrast, submaximal depolarization responses of the slice preparation of the cuneate nucleus of the rat to muscimol were unaffected by 1 pM-1 nM cortisol and only slightly enhanced (about 15%) by 1 microM cortisol. Also, enhancements of 70-120% by 1 microM alphaxalone were undiminished in the presence of 1 microM cortisol. Thus, there is no evidence for a potent effect of cortisol on the GABAA receptor complex in the cuneate nucleus of the rat.
Author List: Andres-Trelles F, Bibby V, Lustman S, Simmonds M A
Publication Types: Comparative Study; Journal Article; Research Support, Non-U.S. Gov't
Substances mentioned in the article: Receptors, GABA-A; Muscimol; Acetylcholine; Corticosterone; Hydrocortisone;
Mesh terms: Acetylcholine/pharmacology; Animals; Cerebellar Nuclei/drug effects; Corticosterone/pharmacology; Female; Guinea Pigs; Hydrocortisone/pharmacology; Ileum/drug effects; In Vitro Techniques; Male; Muscimol/pharmacology; Muscle, Smooth/drug effects; Rats; Receptors, GABA-A/metabolism;