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Orexins/hypocretins regulate drinking behaviour.

K Kunii·A Yamanaka·T Nambu·I Matsuzaki·K Goto·T Sakurai
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Abstract

Orexin/hypocretins are recently identified neuropeptides which regulate feeding behaviour. We found orexins increased water intake when administrated intracerebroventricularly to rats. The effect of orexin-A was more potent as compared with orexin-B, suggesting the possible involvement of OX(1) receptor. The efficacy of orexin-A was almost comparable with that of angiotensin II, and the effect lasted more than 3 h. Prepro-orexin mRNA level was up-regulated when rats were deprived of water. Orexin-immunoreactive varicose axons were observed in the subfornical organ and area postrema, regions implicated in drinking behaviour. These observations suggest a physiological role for orexin as mediators that regulate drinking behaviour.

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Angiotensin IIAnimalsBlotting, NorthernCarrier ProteinsCerebral VentriclesDrinking BehaviorHypothalamic Area, LateralImmunohistochemistryInjections, IntraventricularIntracellular Signaling Peptides and ProteinsMaleNeuropeptidesOrexinsRNA, MessengerRatsRats, WistarStimulation, ChemicalSubthalamusUp-RegulationWater DeprivationJournal ArticleResearch Support, Non-U.S. Gov't

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K Kunii, A Yamanaka, T Nambu, I Matsuzaki, K Goto, T Sakurai. 1999-09-18. Orexins/hypocretins regulate drinking behaviour.. https://doi.org/10.1016/s0006-8993(99)01884-3

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