Increased GABAergic Output in the Ventromedial Hypothalamus Contributes to Impaired Hypoglycemic Counterregulation in Diabetic Rats

摘要

OBJECTIVEImpaired glucose counterregulation during hypoglycemia is well documented in patients with type 1 diabetes; however, the molecular mechanisms underlying this defect remain uncertain. We reported that the inhibitory neurotransmitter γ-aminobutyric acid (GABA), in a crucial glucose-sensing region within the brain, the ventromedial hypothalamus (VMH), plays an important role in modulating the magnitude of the glucagon and epinephrine responses to hypoglycemia and investigated whether VMH GABAergic tone is altered in diabetes and therefore might contribute to defective counterregulatory responses.