Mandelblat-Cerf Yael, Kim Angela, Burgess Christian R, Subramanian Siva, Tannous Bakhos A, Lowell Bradford B, Andermann Mark L
Division of Endocrinology, Diabetes, and Metabolism, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA.
Division of Endocrinology, Diabetes, and Metabolism, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA; Program in Neuroscience, Harvard Medical School, Boston, MA 02115, USA.
Neuron. 2017 Jan 4;93(1):57-65. doi: 10.1016/j.neuron.2016.11.021. Epub 2016 Dec 15.
Ingestion of water and food are major hypo- and hyperosmotic challenges. To protect the body from osmotic stress, posterior pituitary-projecting, vasopressin-secreting neurons (VP neurons) counter osmotic perturbations by altering their release of vasopressin, which controls renal water excretion. Vasopressin levels begin to fall within minutes of water consumption, even prior to changes in blood osmolality. To ascertain the precise temporal dynamics by which water or food ingestion affect VP neuron activity, we directly recorded the spiking and calcium activity of genetically defined VP neurons. In states of elevated osmolality, water availability rapidly decreased VP neuron activity within seconds, beginning prior to water ingestion, upon presentation of water-predicting cues. In contrast, food availability following food restriction rapidly increased VP neuron activity within seconds, but only following feeding onset. These rapid and distinct changes in activity during drinking and feeding suggest diverse neural mechanisms underlying anticipatory regulation of VP neurons.
摄入水和食物是主要的低渗和高渗挑战。为保护身体免受渗透压应激，投射至垂体后叶、分泌血管加压素的神经元（VP神经元）通过改变血管加压素的释放来应对渗透压扰动，而血管加压素控制着肾脏的水排泄。即使在血液渗透压尚未改变之前，饮水后几分钟内血管加压素水平就开始下降。为确定摄入水或食物影响VP神经元活动的精确时间动态，我们直接记录了基因定义的VP神经元的放电和钙活动。在渗透压升高的状态下，水的可获得性在数秒内迅速降低VP神经元活动，在摄入水之前，在出现水预测线索时就开始了。相比之下，食物限制后的食物可获得性在数秒内迅速增加VP神经元活动，但仅在开始进食后。饮水和进食期间这些活动的快速且明显变化表明，VP神经元预期调节存在多种神经机制。
