Release of vasopressin by electrical stimulation of the intermediate portion of the nucleus of the tractus solitarius in rats with cervical spinal cordotomy and vagotomy.

The cervical spinal cord and vagi were severed in anesthetized and artificially ventilated rats. Monopolar electrical stimulation of the intermediate portion of the nucleus of the tractus solitarius (NTS) resulted in subtle increases in concentration of plasma vasopressin (pVP) and in arterial pressure. We suggest that electrical stimulation of the NTS in rats undergoing such surgical preparation to observe the pressor response and/or increase in pVP, represents a rapid approach for screening the neurosecretory function of the central neural integration to release vasopressin.