[Effect of vasopressin and oxytocin on the dorsal root potentials of the isolated perfused spinal cord in rat pups].

The effect of vasopressin and oxytocin on the dorsal root potentials were studied in isolated spinal cord of 12-16 days old rats. It was shown that both neuropeptides evoked reversible depression of the dorsal root potential induced by stimulation of the neighbouring dorsal root. Application of vasopressin or oxytocin caused the reversible dose-dependent depolarization in the dorsal root. The depolarization was preserved in Ca2+-free manganese-containing solution. Functional significance of presynaptic effects of hypothalamic neuropeptides is discussed.