Effects of PK 8165, a partial benzodiazepine receptor agonist, on cholecystokinin-induced activation of hippocampal pyramidal neurons: a microiontophoretic study in the rat.
Benzodiazepines (BZD) have been reported to suppress cholecystokinin-8S (CCK-8S)-induced activation. PK 8165, a ligand of BZD receptors, is an anxiolytic devoid of sedative and anticonvulsant effects. PK 8165, applied microiontophoretically or administered i.v. at low doses, suppressed CCK-8S-induced activation of hippocampal pyramidal neurons, whereas, at high doses it antagonized the effect of microiontophoretic applications of flurazepam. These results indicate that PK 8165 acts as a mixed agonist-antagonist at BZD receptors and suggest that the suppression of CCK-8S-induced activation by BZD might be related to their anxiolytic property rather than to their sedative or anticonvulsant activity.
Bradwejn
J
J
De Montigny
C
C
D000818:Animals; D000927:Anticonvulsants / Q000494:pharmacology*; D001570:Benzodiazepinones / Q000494:pharmacology; D002766:Cholecystokinin / Q000494:pharmacology; D005442:Flumazenil; D005479:Flurazepam / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects*; D007275:Injections, Intravenous; D007478:Iontophoresis; D008297:Male; D009474:Neurons / Q000187:drug effects*; D011712:Pyramidal Tracts / Q000187:drug effects*; D011804:Quinolines / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011963:Receptors, GABA-A / Q000187:drug effects*
D000927:Anticonvulsants; D001570:Benzodiazepinones; D011804:Quinolines; D011963:Receptors, GABA-A; D005442:Flumazenil; D002766:Cholecystokinin; D005479:Flurazepam; C030078:pipequaline