Morphological Changes in the Large Intestine of Rats Subjected to Chronic Restraint Stress and Treated with Selank

We studied the effects of Selank on the condition of the colon wall in Wistar male rats subjected to restraint stress. Selank was injected intraperitoneally in doses of 80, 250, and 750 μg/kg 15 min before stress exposure. In rats subjected to stress, signs of atrophy, inflammatory reaction, and changes in the number and functional activity of mast cells were observed against the background of increased corticosterone level. Selank administration led to a decrease in corticosterone levels, reduced pathomorphological manifestations of stress exposure, and accelerated adaptation. These effects were presumably realized due to multifunctional biological effects of Selank.