Szelényi Z, Zeisberger E, Brück K
Pflugers Arch. 1976 Jul 30;364(2):123-7. doi: 10.1007/BF00585179.
Electrical stimulation in lower brainstem areas presumed to be parts of the ascending noradrenergic system was carried out in the unanaesthetized guinea-pig. In the same animals noradrenaline (NA) was also injected into the anterior hypothalamus. Certain points in the lower brainstem were found, the stimulation of which resulted in a rise of oxygen uptake (more than 60% over the resting level), of body temperature and of electrical muscle activity at an ambient temperature of 29-30 degrees C. Respiratory rate also rose on stimulation, while heart rate did not show a consistent change. All these changes were found to be very similar to those obtained after an intrahypothalamic injection of NA. When the electrical stimulations at the same sites were repeated several times the extent of rise in oxygen uptake became gradually smaller, amounting to only half of the initial response after four periods of stimulation. An intrahypothalamic injection of NA restored the effectiveness of electrical stimulation in the lower brainstem to the original extent. These results suggest that the thermogenesis evoked by the electrical stimulation of these lower brainstem areas may be ascribed to the activation of ascending noradrenergic pathways terminating in the hypothalamus.
在未麻醉的豚鼠身上，对被认为是去甲肾上腺素能系统上行部分的脑干下部区域进行了电刺激。在相同的动物身上，还向前下丘脑注射了去甲肾上腺素（NA）。发现脑干下部的某些点，刺激这些点会导致在29 - 30摄氏度的环境温度下，氧气摄取量增加（超过静息水平60%以上）、体温升高以及肌肉电活动增强。刺激时呼吸频率也会升高，而心率没有呈现出一致的变化。所有这些变化都与下丘脑内注射NA后获得的变化非常相似。当在相同部位重复进行几次电刺激后，氧气摄取量的增加幅度逐渐变小，在经过四个刺激周期后仅为初始反应的一半。下丘脑内注射NA可将脑干下部电刺激的有效性恢复到原来的程度。这些结果表明，对这些脑干下部区域进行电刺激所诱发的产热可能归因于终止于下丘脑的上行去甲肾上腺素能通路的激活。
