Interaction between brain temperature and neuronal excitability

生理脑温度是神经元功能的重要决定因素，温度的变化对海马神经元活动有动态影响已被公认。我之前曾透露，一个温度传感器TRPV4(在34°C以上激活)会被海马神经元中的生理大脑温度激活，从而控制它们在体外的兴奋性。因此，在哺乳动物的大脑中，温度传感器TRPV4可以将温度信息转换为电兴奋性。我在活体中研究了TRPV4是否通过大脑温度激活来调节神经元的兴奋性。我记录了野生型和TRPV4KO小鼠在自由活动条件下的脑电，脑电数据显示TRPV4KO小鼠的海马区活动明显低于WT小鼠。在生理温度下，TRPV4KO海马神经元表现出异常的兴奋性突触后电位(EPSP)，这与脑电数据一致。综上所述，我们首次揭示了在哺乳动物中，TRPV4是从大脑温度到神经元兴奋性的重要翻译。

Physiological brain temperature is an important determinant for neuronal functions, and it is well established that changes in temperature have dynamic influences on hippocampal neuronal activities. I previously revealed that a thermo-sensor TRPV4 (activated above 34°C) is activated by physiological brain temperature in hippocampal neurons and thereby controls their excitability in vitro. Therefore, it is considered that the thermo-sensor TRPV4 can convert temperature information to electrical excitability in mammalian brains. I examined whether TRPV4 regulated neuronal excitability through its activation by brain temperature in vivo. I recorded electroencephalogram (EEG) from wild type and TRPV4KO mice under free moving condition, and the EEG data revealed that hippocampal activities in TRPV4KO mice was significantly reduced compared with those in WT mice. Consistent with the EEG data, TRPV4KO hippocampal neurons exhibited abnormal excitatory postsynaptic potentials (EPSP) at physiological temperature. Taken together, we, for the first time, revealed that TRPV4 is an important translator from brain temperature to neuronal excitability in mammals.