Reversed behavioral effect of cholecystokinin after frontal decortication in rats.
Cholecystokinin tetrapeptide (CCK-4) is likely to possess opposite central action against cholecystokinin octapeptide (CCK-8). In the present study, the behavioral effects of CCK-4 and CCK-8 were compared in frontal decorticated rats. In sham-operated rats, CCK-4 produced marked excitatory responses, while CCK-8 had no stimulatory effects. In frontal decorticated rats, CCK-4 did not cause any excitatory behaviors, while CCK-8 produced markedly enhanced responses. We speculate that an appropriate balance of these CCK peptides might be involved in the maintenance of normal mental states.
Itoh
S
S
Department of Physiology, Kyoto Prefectural University of Medicine, Japan.
Katsuura
G
G
Itoh
T
T
Morimoto
T
T
D000704:Analysis of Variance; D000818:Animals; D002540:Cerebral Cortex / Q000502:physiology*; D002552:Cerebral Ventricles / Q000187:drug effects / Q000502:physiology*; D007276:Injections, Intraventricular; D008297:Male; D009043:Motor Activity / Q000187:drug effects* / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D012844:Sincalide / Q000008:administration & dosage / Q000494:pharmacology*; D013239:Stereotyped Behavior / Q000187:drug effects* / Q000502:physiology; D013758:Tetragastrin / Q000008:administration & dosage / Q000494:pharmacology*
D013758:Tetragastrin; D012844:Sincalide