Ann Nutr Metab. 2018;72 Suppl 2:3-7. doi: 10.1159/000488233. Epub 2018 Jun 20.
Recent experiments using optogenetic tools allow the identification and functional analysis of thirst neurons and vasopressin producing neurons. Two major advances provide a detailed anatomy of taste for water and arginine-vasopressin (AVP) release: (1) thirst and AVP release are regulated not only by the classical homeostatic, intero-sensory plasma osmolality negative feedback, but also by novel, extero-sensory, anticipatory signals. These anticipatory signals for thirst and vasopressin release converge on the same homeostatic neurons of circumventricular organs that monitor the composition of the blood; (2) acid-sensing taste receptor cells (which express polycystic kidney disease 2-like 1 protein) on the tongue that were previously suggested as the sour taste sensors also mediate taste responses to water. The tongue has a taste for water. The median preoptic nucleus (MnPO) of the hypothalamus could integrate multiple thirst-generating stimuli including cardiopulmonary signals, osmolality, angiotensin II, oropharyngeal and gastric signals, the latter possibly representing anticipatory signals. Dehydration is aversive and MnPO neuron activity is proportional to the intensity of this aversive state.
最近使用光遗传学工具的实验允许鉴定和功能分析口渴神经元和血管加压素产生神经元。两个主要进展提供了对水和精氨酸加压素（AVP）释放的味觉的详细解剖学：（1）口渴和 AVP 释放不仅受到经典的稳态、内感觉血浆渗透压负反馈的调节，而且受到新型的外感觉、预期信号的调节。这些口渴和血管加压素释放的预期信号汇聚在监测血液成分的室周器官的相同的稳态神经元上；（2）舌头上的酸感应味觉受体细胞（表达多囊肾病 2 样 1 蛋白）以前被认为是酸味传感器，也介导对水的味觉反应。舌头对水有味道。下丘脑的中脑前核（MnPO）可以整合多种产生口渴的刺激，包括心肺信号、渗透压、血管紧张素 II、口咽和胃信号，后者可能代表预期信号。脱水是令人厌恶的，而 MnPO 神经元的活动与这种厌恶状态的强度成正比。
