The influence of the delta-sleep-inducing peptide on convulsive activity.

Data are presented in this paper on the influence of the delta-sleep-inducing peptide (DSIP) on various forms of convulsive activity. The capacity of this peptide to suppress convulsive activity in foci created in the cerebral cortex by the application of strychnine has been demonstrated in experiments on cats. It has been established in experiments on rats that DSIP determines the later development of the convulsive kindling syndrome, and prevents the development of convulsions in mice induced by bicuculline, picrotoxin, and corazol, but is devoid of such action in relation to thiosemicarbazide and strychnine. It was demonstrated that the anticonvulsant action of DSIP is associated with its influence on the reticular portion of the substantia nigra. The lowest level of this peptide itself has been discovered, in the reticular portion of the substantia nigra at the late stages of pharmacological kindling. It is inferred that DSIP may represent one of the factors of the endogenous control of the excitability of the brain.