[Excitatory effect of tuftsin tetrapeptide on the activity of white rats]

Studies on male white rats have shown that tuftsin (trelys-pro-arg) enhances the locomotion in animals as disclosed by a series of the behavioral tests. The effect is dose-dependent: a dose of 50 microgram/kg did not change any of the test parameters, while that of 150 microgram/kg induced a short-term elevation of locomotion measured with an "Animeks". Administration of tuftsin in a dose of 300 microgram/kg led to the enhancement of the animals' locomotion as measured with the "Animeks", to the increased "open field" running time and to the reduced latent period of the reaction during the training in a T-shaped maze. Also, this dose of the peptide relaxed the reactions associated with fear. It is assumed that the effects observed are consequent on the stimulant action of tuftsin on the body of white rats.