The study of the antidepressant and actoprotective activity of a synthetic analog of the terminal region of neuropeptide Y

Abstract

Topicality. Neuropeptide Y (NPY), which is significantly widespread in the human body, is responsible for various physiological processes, in particular it is involved in the regulation of the emotional behavior, memory and metabolism. The modified short fragment of NPY proposed – NP9 nonapeptide for intranasal administration – shows certain biological properties of the native peptide, in particular the anxiolytic and antiamnesic action. The effect of NP9 on affective disorders of depressive nature and physical endurance remains unknown. Aim. To study the antidepressant and actoprotective activity of NP9 in models of tail suspension, reserpine-induced depression, and forced weighted swimming. Materials and methods. The antidepressant properties of NP9 were studied in the immobilization tail suspension test in mice and on a model of reserpine-induced depression with registration of the body temperature, ptosis, and behavior in the Porsolt forced swimming tests and the open field test. The actoprotective properties of NP9 were studied in the swimming test with a load (10 % of the weight of the animal). Results and discussion. In the tail suspension test, NP9 significantly increased the latent time of the first immobilization compared to the indicators of intact animals (3.2 times) and the imipramine group (2.7 times). NP9 did not significantly affect the manifestations of reserpine-induced depression. These results indicate the weak antidepressant properties of NP9. Nonapeptide significantly increased the swimming time to exhaustion by 2.5 times, indicating actoprotective properties, according to which NP9 exceeded the reference drug Semax. Conclusions. In the tail suspension test, nonapeptide NP9 exhibits dose-dependent antidepressant properties after the first administration, but this effect is practically not manifested in the rigid reserpine-induced model of depression. NP9 increases the physical endurance of animals in the forced weighted swimming test and is superior to the reference drug Semax by its effectiveness.