Reversibility of the blood-brain barrier dysfunction induced by acute hypertension.

An acute hypertensive episode of short duration (less than 3 min) induced by i.v. injection of angiotensin in rats resulted in a blood-brain barrier dysfunction that was rapidly reversible. Thus, no macroscopic extravasation was seen when Evans blue was given 10 or 20 min after angiotensin. A faint fluorescence (Evans blue-albumin) was seen in the walls of some intracerebral arterioles in a few rats given the tracer 10 min after angiotensin.