Effect on blood glucose concentration of changes in availability of glucose to the brain

¹ Harrison Department of Surgical Research and Department of Neurosurgery, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania

In the unanesthetized rabbit, systemic blood glucose concentration was measured periodically during the course of a slow, continuous infusion of glucose solution via the internal carotid artery. Under conditions otherwise identical, the same experiment was performed in the same rabbit, but the infusion was intravenous. In 7 of 14 such pairs of experiments, the curve of glucose concentration versus time was significantly lower for the intracarotid experiment and in the other seven cases there was no significant difference between the two curves. These results suggest that the brain responds to the increased concentration of glucose of its environment and by some mechanism acts to return it toward normal. Experiments were done in the same way with 2-deoxy-d-glucose, a substance which produces a cellular glucopenia. Of seven pairs of experiments, the systemic blood glucose curve was markedly higher in intracarotid infusion in three cases, moderately higher in two cases, and not significantly different in two cases from the curve for the intravenous infusion. These results suggest that the brain responds to decreased availability of glucose and acts, by way of the sympathetic nervous system, to raise the blood glucose concentration.

This article has been cited by other articles:

				S. Woods and L. McKay Intraventricular alloxan eliminates feeding elicited by 2-deoxyglucose Science, December 15, 1978; 202(4373): 1209 - 1211. [Abstract] [PDF]

				C. J. Goodner and W. A. Tustison Autonomic Mediation of the Effect of Raised Arterial Glucose upon Free Fatty Acids Science, November 6, 1964; 146(3645): 770 - 772. [Abstract] [PDF]