Alteration of the expression of the hypocretin (orexin) gene by 2-deoxyglucose in the rat lateral hypothalamic area

Following an i.p. injection of 2-deoxyglucose (2DG), a nonmetabolizable ana logue of glucose known to induce intracellular glucopenia, a progressive de crease in the level of hypocretin (Hcrt)/orexin mRNA was observed in the ra t lateral hypothalamus while the melanin-concentrating hormone (MCH) expres sion in neighbouring neurons remained unaffected. This result together with the previously reported stimulation of Hcrt expression by insulin confirms that Hcrt neurons, but not MCH neurons, are sensitive to glucose availabil ity and suggests that they respond through different mechanisms and/or diff erent pathways to intracellular glucopenia and hypoglycemic conditions. Neu roReport 11:531-533 (C) 2000 Lippincott Williams & Wilkins.