BEHAVIORAL-EFFECTS OF THE CYCLIC CHOLECYSTOKININ PEPTIDE ANALOG JMV-320

The in vivo effects of JMV-320 (a highly selective CCKB receptor ligan d) and of CCK-4 on exploratory activity and memory in rats were compar ed. JMV-320 and CCK-4 did not modulate exploratory activity in an open field test but decreased it in an elevated plus-maze. CCK-4 (50 mu g/ kg) impaired passive avoidance response 3 h after training and JMV-320 (1 and 10 mu g/kg) decreased active avoidance response 24 h after tra ining. The behavioral effects of JMV-320 resemble the effects of CCK-4 and suggest that in vivo JMV-320 acts as a CCKB receptor agonist.