Abstract
Conscious rats and rats under N2O anesthesia were subjected to blood pressure elevations by injection of epinephrine, bicuculline and amphetamine. Mean arterial pressure was measured from a chronic indwelling cannula in the aorta in awake rats. The protein leakage in the brains was studied using Evans blue and 125IHSA [human serum albumin]. Conscious animals developed less blood-brain barrier dysfunction than anesthetized ones. The largest difference was obtained with amphetamine and the smallest with epinephrine. Possible explanations to the results are discussed.