Increased blood pressure responses to central angiotensin II in spontaneously hypertensive rats

The blood pressure responses following infusions of angiotensin II (ANG II) into the brain ventricles (i.v.t.) have been tested in spontaneously hypertensive (SH) rats and in normotensive Wistar Kyoto (WK) rats. The mean arterial blood pressure increases were significantly higher in SH rats than in WK rats. Propranolol treatment reduced blood pressure increases to i.v.t. ANG II in WK, but not in SH rats. The higher sensitivity to i.v.t. ANG II in SH rats supports a role of central ANG II in the maintenance of high blood pressure in SH rats.