Delta sleep-inducing peptide as a factor increasing the content of substance P in the hypothalamus and the resistance of rats to emotional stress.

The influence of delta sleep-inducing peptide (DSIP, 60 and 120 nmole/kg, intraperitoneally) on the content of substance P (SP) in the hypothalamus of rats was studied in male rats of the August line. It was demonstrated that the administration of DSIP significantly increases the average content of SP in the hypothalamus, as well as its content in animals resistant to and predisposed to emotional stress. A daily one-time administration of DSIP before placing the rats in conditions of stress increases the content of SP in the hypothalamus which was decreased during emotional stress. The preliminary one-time administration of DSIP to animals subjected to a stressor influence also increases the SP content in the hypothalamus. It was established that a one-time administration of DSIP in a dose of 60 nmole/kg sharply decreases the classical manifestations of stress such as the hypertrophy of the adrenals and involution of the thymus.