Memory impairments induced by peripherally administered cholecystokinin a‐type receptor antagonists in rats

Abstract

Abstract Intraperitoneal injection of cholecystokinin (CCK) A‐type receptor antagonists, L‐364,718 and CR 1409, caused dose‐dependent memory impairments in passive and active avoidance responses and in Morris water pool test in rats. These antagonist effects were significant at a dose of 1 mg/kg, while with proglumide, 50–100 mg/kg were required to produce a similar memory deficit. The results suggest that loss of biologically active CCK octapeptide (CCK‐8), not only in the brain but also in the peripheral tissues, causes memory impairmets in rats. © 1992 Wiley‐Liss, Inc.