Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT, USA.
Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA.
Science. 2024 Nov 29;386(6725):1048-1055. doi: 10.1126/science.adp8358. Epub 2024 Nov 28.
Water deprivation is a life-threatening condition that engages a protective physiological response to couple osmolyte retention with potentiation of thirst. This response, typical for most mammals, safeguards against short-term water deprivation but fails in the long term. Thirteen-lined ground squirrels () use the short-term response during summer, whereas during winter, they lack thirst and survive without water for months. In this work, we show that long-term thirst suppression occurs despite hormonal and behavioral signs of a substantial fluid deficit and originates from hypoactivity of neurons in the circumventricular organs, which exhibit marked functional suppression during winter that blunts their sensitivity to thirst cues. Our work reveals a notable capacity of the evolutionarily conserved brain regions that control fluid homeostasis in mammals to enable long-term survival without water.
水剥夺是一种危及生命的状况，它引发了一种保护性的生理反应，使渗透物保留与口渴增强相结合。这种反应在大多数哺乳动物中很典型，可保护它们免受短期水剥夺的影响，但在长期内却失败了。十三线地松鼠（）在夏季使用短期反应，而在冬季，它们没有口渴感，可以在没有水的情况下存活数月。在这项工作中，我们表明，尽管存在大量液体缺乏的激素和行为迹象，但长期抑制口渴仍会发生，这源于室周器官神经元的活动减少，这些神经元在冬季表现出明显的功能抑制，从而削弱了它们对口渴线索的敏感性。我们的工作揭示了控制哺乳动物体内液体平衡的进化上保守的脑区的显著能力，使它们能够在没有水的情况下长期生存。
