Tanaka H, Ishikawa Y, Nakayama T
Department of Physiology, Osaka University Medical School, Japan.
Physiol Behav. 1988;42(6):605-11. doi: 10.1016/0031-9384(88)90164-3.
We investigated the effects of current intensity on behavioral and autonomic heat-loss responses in intracranial self-stimulating (ICSS) rats. At an ambient temperature (Ta) of 22 degrees C, the tail vasodilation during ICSS behavior began at higher hypothalamic temperature (Thy) at higher current intensity. At a Ta of 36 degrees C, body extension, a typical heat-loss response in rats, appeared during ICSS behavior and frequently interrupted lever pressing. When the body extension first began, Thy was elevated if current intensity was high. In experiments in which current intensity was varied between two levels at a Ta of 22 degrees C, if current intensity was lowered after tail vasodilation began and Thy reached a steady level, the rat interrupted pressing the lever to lose heat through grooming or body extension. Rectal temperature (Tre) dropped in the process. If, on the other hand, current intensity was raised, the rate of lever pressing increased and Tre rose with tail vasoconstriction. The data suggest that the magnitude of the reward, as reflected in current intensity, affects both behavioral and autonomic heat-loss responses.
我们研究了电流强度对颅内自我刺激（ICSS）大鼠行为和自主散热反应的影响。在环境温度（Ta）为22摄氏度时，ICSS行为期间的尾部血管舒张在较高电流强度下始于较高的下丘脑温度（Thy）。在Ta为36摄氏度时，大鼠典型的散热反应——身体伸展，出现在ICSS行为期间，并频繁中断杠杆按压。当身体伸展首次开始时，如果电流强度高，Thy会升高。在Ta为22摄氏度时电流强度在两个水平之间变化的实验中，如果在尾部血管舒张开始且Thy达到稳定水平后降低电流强度，大鼠会中断杠杆按压，通过梳理毛发或身体伸展来散热。在此过程中直肠温度（Tre）下降。另一方面，如果提高电流强度，杠杆按压频率增加，Tre随着尾部血管收缩而升高。数据表明，电流强度所反映的奖励大小会影响行为和自主散热反应。
