1824-P: Leptin Receptor Neurons in the Hypothalamic Ventromedial Nucleus Play a Physiological Role in Regulating Glucose Tolerance

A role for leptin receptor (LepR)-expressing neurons in the hypothalamic ventromedial nucleus (VMN) in glucose homeostasis is suggested by studies in which leptin is administered into, or leptin receptors are deleted from, this brain area. However, whether LepR neurons in the VMN play a physiological role in glycemic control remains unknown. To test this hypothesis, we utilized an optogenetics approach to acutely silence VMNLepR neurons in awake, freely moving mice. We found that while photoinhibition of VMNLepR neurons had no effect on blood glucose levels under basal conditions (Control AUC: 681.6 ± 422.4 vs. Inhib AUC: 565.8 ± 350.7; p=ns, n=10), it impaired glucose tolerance significantly (Control AUC: 9251.7 ± 2032.6 vs. Inhib AUC: 13957.4 ± 4837; p