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5-HT2CRs expressed by pro-opiomelanocortin neurons regulate energy homeostasis.

ABSTRACT: Drugs activating 5-hydroxytryptamine 2C receptors (5-HT2CRs) potently suppress appetite, but the underlying mechanisms for these effects are not fully understood. To tackle this issue, we generated mice with global 5-HT2CR deficiency (2C null) and mice with 5-HT2CRs re-expression only in pro-opiomelanocortin (POMC) neurons (2C/POMC mice). We show that 2C null mice predictably developed hyperphagia, hyperactivity, and obesity and showed attenuated responses to anorexigenic 5-HT drugs. Remarkably, all these deficiencies were normalized in 2C/POMC mice. These results demonstrate that 5-HT2CR expression solely in POMC neurons is sufficient to mediate effects of serotoninergic compounds on food intake. The findings also highlight the physiological relevance of the 5-HT2CR-melanocortin circuitry in the long-term regulation of energy balance.

SUBMITTER: Xu Y

PROVIDER: S-EPMC2631191 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature

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5-HT2CRs expressed by pro-opiomelanocortin neurons regulate energy homeostasis.

Xu Yong Y Jones Juli E JE Kohno Daisuke D Williams Kevin W KW Lee Charlotte E CE Choi Michelle J MJ Anderson Jason G JG Heisler Lora K LK Zigman Jeffrey M JM Lowell Bradford B BB Elmquist Joel K JK

Neuron 20081101 4

Drugs activating 5-hydroxytryptamine 2C receptors (5-HT2CRs) potently suppress appetite, but the underlying mechanisms for these effects are not fully understood. To tackle this issue, we generated mice with global 5-HT2CR deficiency (2C null) and mice with 5-HT2CRs re-expression only in pro-opiomelanocortin (POMC) neurons (2C/POMC mice). We show that 2C null mice predictably developed hyperphagia, hyperactivity, and obesity and showed attenuated responses to anorexigenic 5-HT drugs. Remarkably, ...[more]

PMID: 19038216

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