| Abstract: | Vasopressin causes motor disturbances following intracerebroventricular injections and a second central injection results in an apparent sensitization of the animal to the convulsant effect of vasopressin. In this study, the effect of vasopressin pretreatment on the central and peripheral pressor effects of vasopressin was examined in Sprague-Dawley rats. There was no increase in the responsiveness to the pressor effects of vasopressin, either central or peripheral, in animals that had previously received central vasopressin. This evidence suggests that the phenomenon of increased sensitivity to vasopressin is not displayed by all vasopressin's actions. |
