Effect of vasopressin and oxytocin perfusion of the cerebral ventricles on evoked tongue jerks.

The effect of increased concentration of vasopressin and oxytocin in the cerebrospinal fluid on the excitability of the hypoglossal nerve nucleus was investigated. The experiments were carried out on rats under chloralose anaesthesia. Retractory jerks of the outstretched tongue were evoked by supra- or infraorbital nerve stimulation during perfusion of the cerebral ventricles with McIlwain-Rodnight solution. The solution contained synthetic arginine vasopressin 0.05 U/ml or synthetic oxytocin 0.05 U/ml. Perfusion of the ventricles with vasopressin increased and perfusion with oxytocin decreased the evoked tongue jerks.