Activating glucose transporter 2 positive neurons stimulates cerebral blood flow

Glucose transporter 2 (Glut2)-positive cells are sparsely distributed in brain and play an important role in the stimulation of glucagon secretion in response to hypoglycemia. The effect on CBF of optogenetic activation of hypoglycemia responsive Glut2-positive neurons of the paraventricular thalamic area was measured in mice expressing channelrhodopsin2 under the control of the Glut2 promoter. Optogenetic activation of Glut2-positive neurons in the paraventricular thalamic nucleus induced a local CBF change similar in magnitude to the effect of hypoglycemia. Thus, our data indicate that brain Glut2-positive neurons are key regulators of hypoglycemia-induced activation of CBF.