Blood-brain barrier to albumin in awake rats in acute hypertension induced by adrenaline, noradrenaline or angiotensin.

Acute hypertension was induced by adrenaline, noradrenaline or angiotensin in awake unrestrained rats with chronic indwelling catheters in a jugular vein and in the aorta. The leakage of 125IHSA (human serum albumin) into the brains from rats given adrenaline was significantly larger than in the brains from rats given noradrenaline or angiotensin. It is likely that the enhanced vulnerability of the blood-brain barrier to an adrenaline-induced increase in blood pressure is due to the beta-adrenergic stimulating effect of adrenaline.