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Hypothalamic tanycytes generate acute hyperphagia through activation of the arcuate neuronal network.

ABSTRACT: Hypothalamic tanycytes are chemosensitive glial cells that contact the cerebrospinal fluid in the third ventricle and send processes into the hypothalamic parenchyma. To test whether they can activate neurons of the arcuate nucleus, we targeted expression of a Ca2+-permeable channelrhodopsin (CatCh) specifically to tanycytes. Activation of tanycytes ex vivo depolarized orexigenic (neuropeptide Y/agouti-related protein; NPY/AgRP) and anorexigenic (proopiomelanocortin; POMC) neurons via an ATP-dependent mechanism. In vivo, activation of tanycytes triggered acute hyperphagia only in the fed state during the inactive phase of the light-dark cycle.

SUBMITTER: Bolborea M

PROVIDER: S-EPMC7322081 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Hypothalamic tanycytes generate acute hyperphagia through activation of the arcuate neuronal network.

Bolborea Matei M Pollatzek Eric E Benford Heather H Sotelo-Hitschfeld Tamara T Dale Nicholas N

Proceedings of the National Academy of Sciences of the United States of America 20200608 25

Hypothalamic tanycytes are chemosensitive glial cells that contact the cerebrospinal fluid in the third ventricle and send processes into the hypothalamic parenchyma. To test whether they can activate neurons of the arcuate nucleus, we targeted expression of a Ca<sup>2+</sup>-permeable channelrhodopsin (CatCh) specifically to tanycytes. Activation of tanycytes ex vivo depolarized orexigenic (neuropeptide Y/agouti-related protein; NPY/AgRP) and anorexigenic (proopiomelanocortin; POMC) neurons via ...[more]

PMID: 32513737

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