INHIBITION OF POTASSIUM-EVOKED RELEASE OF CHOLECYSTOKININ FROM RAT CAUDATE-PUTAMEN, CEREBRAL-CORTEX AND HIPPOCAMPUS INCUBATED INVITRO BY PHENCYCLIDINE AND RELATED-COMPOUNDS

Potassium-evoked release of cholecystokinin (CCK) from slices of caudate-putamen, hippocampus, and cerebral cortex was inhibited in a dose-related fashion by phencyclidine (PCP). In order to further examine this effect, PCP-like ligands (dexoxadrol, levoxadrol, PCMP and MK-801) as well as compounds known to interact with the sigma receptor ((+)-SKF, DTG, (+)-3-PPP,n and pentazocine) were tested. While some of these compounds inhibited CCK release, their rank order potency (Dex = Lev > PCP > PCMP > DTG = MK-801 = (+)-3-PPP) differs from that of known PCP-N-methyl-d-aspartate linked effects or sigma interactions. These results suggest that the mechanism by which PCP acts to inhibit CCK release may involve a novel type of PCP interaction. © 1990.