Autoregulation of Cerebral Circulation

Autoregulation of cerebral circulation is the mechanism by which the cerebral blood flow (CBF) is maintained constant between large limits of arterial pressure. Autoregulation appears only between certain pressure limits. The specialized literature presents 2 possible mechanisms of autoregulation: myogenic reaction and metabolic regulation. Sympathetic nervous system stimulation and the antagonism of reninangiotensin system modulate CBF autoregulation, switching the curve to higher or smaller values of arterial pressure. Cerebral autoregulation is dependent on intracranial pressure as well on venous pressure. This paper is a review of the main mechanisms involved in cerebral autoregulation, its limits in hypertension, of the morphological changes in cerebral arteries and its assessment.