The aim of the study was to test the influence of tuftsin analogue TP- 1, its terminal fragment- tetrapeptide Arg-Pro-Gly-Pro and L-arginine on the escape reaction induced by electric stimulation of nucleus ventromedialis of the hypothalamus (Vmh). The experiments were carried out on 29 male rabbits of the Chinchilla breed (2900-3500g). The studied substances were administered in doses of 0.5 μmol/kg of body weight into lateral cerebral ventricle (icv). The period of experiment (3h) was divided into 10-min intervals. Vmh stimulation was performed every 10 min (18 stimulations). The latency time (LT) of escape reaction was considered to be the period between the beginning of Vmh stimulation and the escape reaction. Each of tested substances caused a significant increase of LT of the escape reaction. The increase of LT after icv administration of L-arginine was statistically smaller than the increase of LT after icv administration of tetrapeptide and TP-1.