Nishino H
Nihon Yakurigaku Zasshi. 1976 Nov;72(8):941-54. doi: 10.1254/fpj.72.941.
Unit activity of lateral hypothalamic area (LHA) and ventromedian nuclei (VMN) was recorded in urethane anesthetized male rats. A 5 to 10 sec, a 3 to 5 min and a circadian rhythmicity were observed. In about 15% of all neurons, spontaneous activity of LHA and VMN showed reciprocal relationships. Subthreshold stimuli applied at a slow rate in the septum and the suprachiasmatic nuclei (SCN) suppressed the rhythms without changing firing rates. On the other hand stimulation of the optic nerve at a rate of 5 to 10/sec increased firing rates in one third of neurons of SCN. Iontophoretically applied acetycholine increased 80% of tested neurons of SCN, whereas norepinephrine, dopamine and 5HT inhibited 64%, 60% and 75% of SCN neurons, respectively. These inhibitions were much stronger in neurons, the activity of which was increased by optic nerve stimulation. Stimulation of the SCN inhibited the tonic activity in cervical sympathetic nerves. These data suggest that SCN plays a significant role in controlling the rhythmic activity of LHA, VMN and the pineal gland. Dopamine and 5HT may be involved in regulation of the firings of SCN neurons.
在氨基甲酸乙酯麻醉的雄性大鼠中记录下丘脑外侧区（LHA）和腹内侧核（VMN）的单位活动。观察到5至10秒、3至5分钟和昼夜节律。在所有神经元中约15%，LHA和VMN的自发活动呈现相互关系。以缓慢速率施加于隔区和视交叉上核（SCN）的阈下刺激抑制了节律，而不改变放电率。另一方面，以每秒5至10次的速率刺激视神经，使SCN三分之一的神经元放电率增加。离子电泳施加乙酰胆碱使80%的受试SCN神经元增加，而去甲肾上腺素、多巴胺和5-羟色胺分别抑制64%、60%和75%的SCN神经元。在视神经刺激使其活动增加的神经元中，这些抑制作用更强。刺激SCN抑制颈交感神经的紧张性活动。这些数据表明，SCN在控制LHA、VMN和松果体的节律性活动中起重要作用。多巴胺和5-羟色胺可能参与SCN神经元放电的调节。
