INVOLVEMENT OF THE PVN AND BST IN 1K1C HYPERTENSION IN THE RAT

The paraventricular nucleus of the hypothalamus (PVN) and the bed nucleus of the stria terminalis (BST) are two sources of central nervous system (CNS)-derived arginine vasopressin (AVP), a nonapeptide that has been implicated in central autonomic regulation and in particular in cardiovascular regulation, through its actions within the CNS. These experiments were designed to determine if either the PVN or the BST were involved in the development of Goldblatt one-kidney one-clip (1K1C) hypertension in the rat. In order to test this hypothesis, ibotenic acid lesions of the PVN or electrolytic lesions of the BST were undertaken in both normotensive (sham-operated) rats and in 1K1C rats. In both cases the development of 1K1C hypertension was inhibited over the 18-21 days following surgery. Lesions of the PVN did not alter normal blood pressure regulation in the sham-operated animals, whereas lesions to the BST did affect normal blood pressure regulation, resulting in a dramatic increase in blood pressure during the initial days following surgery. These studies suggest that the PVN and BST are involved in the development of 1K1C hypertension in the rat, moreover the BST may also play a role in central cardiovascular control.