Cerebral blood flow regulation: Vascular resistance adjustments in the circle of willis

Abstract

Continuous measurements of systemic blood pressure (BP), cerebral perfusion pressure and CBF were accomplished in the cal during transient hypertension, hypercapnia and bilateral carotid arlery occlusion. From these measurements resistance values in the circle of Willis and in the cerebral arteries distal to the circle were calculated. The results indicate that the arteries of the circle of Willis and the arteries distal to the circle of Willis dilate and contract independently. © 1976 American Heart Association, Inc.