Amelioration of cerebral ischemia by prior treatment of hypertension.

Bilateral carotid artery ligation was made in 14 SHR while rCBF was serially measured with hydrogen clearance. Blood pressure was controlled with an intra-arterial catheter connected to a reservoir. There was no significant correlation between blood pressure and rCBF prior to the carotid occlusion, but afterwards there was a progressively increasingly negative correlation between mean arterial blood pressure and rCBF with time. These observations indicate that the severity of ischemia is greater in the presence of hypertension if the hypertension is present prior to the onset of ischemia and the blood pressure maintained constant thereafter.