Attenuation by arginine- and desglycinamide-lysine-vasopressin of a centrally evoked pressor response.

Arginine8-vasopressin (AVP) administered in a lateral cerebral ventricle attenuated the pressor response evoked by electrical stimulation of the mesencephalic reticular formation (MRF) in urethane-anesthetized rats. The blockade appeared to be dose-dependent in the range of 3-25 ng. The maximal effect was a 40% reduction of the pressor response. Desglycinamide9-lysine8-vasopressin (DG-LVP) exerted a similar effect on the pressor response. Both AVP and DG-LVP failed to affect basal blood pressure upon intraventricular administration. It is suggested that centrally acting neuropeptides related to vasopressin affect brain mechanisms involved in the regulation of blood pressure.