Neural mechanisms which induce blood pressure fluctuation during REM sleep

在REM睡眠期间，内稳态系统不显示正常的性能，自主神经系统出现大的波动。关于这种波动是如何产生的机制以及这种波动的生理意义知之甚少。本研究旨在探讨下丘脑和脑干在REM睡眠期血压波动调节中的关系，主要结果如下：1.在乌拉坦麻醉大鼠下丘脑，用油压操纵器移动碳纤维电极，每隔200-400 μm电刺激一次。刺激外侧下丘脑及其周围区域后，血压升高，刺激该有效区域后，血压降低.神经元活动记录从未麻醉的头部约束大鼠同时血压。部分LHA神经元与REM睡眠期血压升高密切相关。3.近年来，我们发现被盖背外侧核（LDT）内的胆碱能神经元与REM睡眠期血压升高相关。因此，今年，我们进行了LHA和LDT的同步记录，发现当REM睡眠期间血压升高时，LDT神经元的活动先于LHA神经元的活动。这些结果表明，对于REM睡眠期间的血压波动，LDT到LHA的兴奋性输入起着至关重要的作用。

During REM sleep, the homeostasis system does not show normal performance and large fluctuations of autonomic nervous systems appear. Little is known on the mechanisms how this fluctuation is generated and on the physiological significance of this fluctuation. In this study, the experiments were performed to elucidate the relationship of the hypothalamus and the brainstem for the regulation of blood pressure fluctuation during REM sleep, and we got the following results ;1. The hypothalamus of urethane anesthetized rats was electrically stimulated every 200-400 μm through a carbon fiber electrode which was moved by oil-pressure manipulator. Blood pressure increase was induced after the stimulation to the lateral hypothalamus (LHA) and its surroundings, while posterior to this effective area, blood pressure decrease was induced.2. Neuronal activity was recorded from unanesthetized head-restrained rats simultaneously with blood pressure. Some of the LHA neurons show close correlation with blood pressure increase during REM sleep.3.Last year, we found that the cholinergic neurons in the laterodorsal tegmental nucleus (LDT) showed the correlation with blood pressure increase during REM sleep. So, this year, we performed simultaneous recording from the LHA and LDT and found that when the blood pressure increase during REM sleep, the activity of the LDT neurons preceded that of the LHA neurons.These results suggest that for blood pressure fluctuation during REM sleep, the excitatory input from the LDT to the LHA have a crucial role.