Hemiinfusion of the brain in rats: blood-to-brain penetration.

Abstract

A technique has been developed by which a chemical agent infused into an internal carotid artery of the rat is restricted in its distribution to the homolateral side of the brain. The infused solution dilutes the internal carotid blood by less than 15% so that supplies of oxygen and blood constituents are near normal. The technique is relatively simple and produces minimal distortion of brain structure and function. Tritiated 3-O-methylglucose, injected intravenously, penetrated into both sides of the brain at equal rates when glucose-free Locke solution was infused into both internal carotid arteries. When D-glucose or D-mannose was infused into one carotid artery, at rates sufficient to give internal carotid blood levels of approximately 10-2 M, the rate of penetration of 3-O-methylglucose into the homolateral side of the brain was significantly reduced compared to the opposite (control) side on which glucose-free Locke solution was infused. These results are consistent with the hypothesis that a carrier mechanism is involved in the trans-location of 3-O-methylglucose across the blood-brain interface.