Influence of oligopeptides, the fragment and analogue 4-10 of corticotropin, on the behaviour of rabbits under spontaneous conditions

Short peptides of corticotropin derivatives, fragment 4-10 and its analogue 4-10, were administered to rabbits into the lateral cerebral ventricle (icv) in a dose of 0.5 nmol/kg b.w. It was proved that the fragment and analogue significantly modified the animals' behaviour. The difference in the activity between the fragment and its analogue was noted. The slighter influence of the analogue was caused by the change of C-terminal fragment of oligopeptide sequence. The peptides significantly prolonged the comfort and grooming time in general structure of the behaviour by intensifying and conditioning the reactions that reduced the influence of stressing factors causing the changes in animal patterns of the behaviour. The tested synthetic tripeptide Pro-Gly-Pro showed a very weak activity and only slightly changed the behaviour profile.