Responses of subfornical organ neurons to cardiovascular-related peptides and their intracellular second messenger system

穹窿下器（SFO）在中枢心血管控制和饮酒行为中起重要作用，并调节精氨酸加压素和催产素的释放。本研究旨在阐明（1）神经元的基本电生理特性，（2）SFO的突触输入，（3）血管紧张素II（AII）的作用，（4）γ-氨基丁酸（GABA）对SFO神经元的作用。为了这些目的，使用大鼠SFO的切片制备和常规细胞内记录。半数SFO神经元自发放电，大多数神经元有异常内向整流和低阈值钙峰。SFO分别通过谷氨酸和GABA接受兴奋性和抑制性突触输入。所有兴奋大多数SFO神经元关闭钾通道或开放的非选择性阳离子通道。血液中的All似乎影响SFO神经元，但不影响神经元的All。GABA通过GABAA受体发送抑制性突触输入并激活氯离子通道。

The subfornical organ(SFO) takes an important role in central cardiovascular control and drinking behavior, and modulates release of arginine vasopressin and oxytocin. This study is designed to elucidate(1) basic electrophysiological properties of the neurons,(2) synaptic inputs to the SFO,(3) effects of angiotensin II(AII) and(4) effects of gamma-animobutyric acid (GABA) on the SFO neurons. For these purposes, slice preparation of the SFO of rats and conventional intracellular recordings were used. Half of SFO neurons fired spontaneously and most neurons had anomalous inward rectification and low threshold calcium spike. The SFO received excitatory and inhibitory synaptic inputs, through glutamic acid and GABA, respectively. All excited most SFO neurons with either closing of potassium channels or opening of non-selective cation channels. The blood-born All seems to affect the SFO neurons, but not the neuronal All. GABA sends inhibitory synaptic inputs through GABAA receptors and activates chloride channels.