Article date: 1992/9/1
PubMed ID: 1335797
Journal name: Biulleten' eksperimental'noi biologii i meditsiny (ISSN: 0365-9615)
Effects of corazol (pentylenetetrazole, PTZ) on the GABAA receptor-channel complex mediated 36Cl- influx into synaptoneurosomes isolated from rat cerebral cortex, were studied. PTZ inhibited the 36Cl- influx stimulated by a GABA agonist, muscimol, concentration-dependently with an IC50 of 2.11 +/- 0.25 mM. In addition, the rate of muscimol-dependent desensitization of the GABAA receptor-channel complex was significantly reduced in the presence of PTZ. Apparently, the superimposition of these two mutually opposing effects is the cause of a mixed (competitive/noncompetitive) type of inhibition displayed by PTZ. The rate of desensitization of GABAA receptor-channel complex is suggested to be regulated by intracellular concentration of Cl- through a feed-back mechanism.
Author List: Kryzhanovskiĭ G N, Rebrov I G, Glebov R N
Publication Types: Comparative Study; English Abstract; Journal Article
Substances mentioned in the article: GABA-benzodiazepine receptor-chloride ionophore complex; Receptors, GABA-A; Muscimol; Pentylenetetrazole;
Mesh terms: Animals; Cerebral Cortex/drug effects; Feedback; In Vitro Techniques; Male; Muscimol/pharmacology; Pentylenetetrazole/pharmacology; Rats; Receptors, GABA-A/metabolism; Stimulation, Chemical;