Effects of Increased Blood Pressure on Cerebral Vessels in Mice

THE PURPOSE of this report is to describe the effects of acute and chronic elevations of blood pressure upon the diameter and reactivity of pial blood vessels, and to describe the presence of cerebral edema in chronic hypertension, a finding that may be related to alterations of vascular permeability. It is necessary to describe and to discuss sequentially the effects of both acute and chronic elevations in blood pressure because observations made in the acute situation have been considered useful in interpreting phenomena seen in the chronic state.^1-3 Other studies, similar in part to this one, have been carried out by Fog,^4-6 Forbes et al,⁷ Byrom,¹ and Meyer et al^2,3; however, the present communication differs in several respects from previous reports. When the effects of acute elevations are considered, only the papers of Fog^4-6 systematically describe the variable alterations in diameter that follow the