Melanin-concentrating hormone expression in slice cultures of rat hypothalamus is not affected by 2-deoxyglucose

In rats, melanin-concentrating hormone (MCH) neurons are mainly located wit hin the lateral hypothalamic area (LHA). This area is known to be involved in the control of feeding and to contain glucose-sensitive cells. As a role for MCH in the regulation of food intake has been reported, we investigate d the effects of a-deoxyglucose (2DG) on MCH expression in cultured LHA sli ces, to verify if MCH neurons are sensitive to local glucoprivation through a modulation of MCH synthesis. After a 2-10 h 2DG incubation, competitive reverse transcription-polymerase chain reaction (RT-PCR) did not show any v ariation of MCH mRNA; no change was also observed in MCH immunocytochemical labeling, A slight decrease of MCH mRNA (5-15%) after a 17 h 2DG treatment might be due to a general degradation of neurons induced by long-term gluc oprivation. In conclusion, we suggest that MCH neurons are not the glucose- sensitive cells previously described in the LHA and that the signals induci ng their previously reported response to glycemia variations do not arise f rom the LHA itself. (C) 1999 Elsevier Science Ireland Ltd. All rights reser ved.