Cerebral circulation and norepinephrine: relevance of the blood-brain barrier

摘要: The systemic administration of norepinephrine has minimal effects on the cerebral circulation, perhaps due to blood-brain barrier mechanisms. To test hypothesis, cerebrovascular beyond were studied in anesthetized baboons, Intraventricular (40 mug/kg) resulted significant increases blood flow (40%), oxygen consumption (21%), and glucose uptake (153%). Intracarotid hypertonic urea opens by osmotic disruption; Consequent urea, intracarotid infusion norepinephrine, 50 ng/kg-min, significantly increase (49%), (76%), It appears probable that responses are dependent integrity barrier; is likely flow, associated with when it bypasses barrier, secondary an metabolism.