MODIFICATION OF NYCTHEMERAL VARIATIONS IN BODY CORE TEMPERATURE AFTER DAILY EXERCISE AT A FIXED TIME

本研究旨在研究每天在固定时间进行几个小时的运动如何改变大鼠身体核心温度和行为的昼夜变化模式。采用自发跑轮作为运动模式，以避免对大鼠造成任何人为压力。雄性Wistar大鼠适应于带滚轮的笼子。然后，将大鼠的运动时间限制在暗期的前3或后3或6h。在两周的活动限制后，大鼠再次被允许自由接触轮子。结论：1.活动限制后，大鼠前一跑时对应时段的车轮转数明显增加。雄性Wistar大鼠被关在有转轮的笼子里，在黑暗阶段的后半部分，允许接触转轮6小时。在三周的运动期后，他们被拒绝在方向盘上跑步。在黑暗阶段的后半部分，它们的身体核心温度显著升高2-3小时。结果表明，在大鼠中，每天限定固定时间的自愿跑步改变了大鼠身体核心温度和运动活动的夜间变化模式，即在先前允许运动的时间内，身体核心温度和跑步活动增加。

The present study was conducted to examine how daily exercise for several hours at a fixed time modifies the pattern of day-night variations in body core temperature and behavior in rats. Spontaneous wheel running was adopted as a model of exercise to avoid any artificial stress on rats.1. Male Wistar rats were acclimated to cages with a running wheels. Then, the running time of rats were limited to the first or last 3 or 6 h of the dark phase. After a 2-week activity restriction, the rats were again allowed access to the wheel freely. Wheel revolutions of rats during the period corresponding to the previous running time significantly increased after the activity restriction.2. Male Wistar rats were kept in cages with a running wheel and allowed access to the wheel for 6 h in the last half of the dark phase. After a 3-week exercise period, they were denied to run in the wheel. Their body core temperature significantly increased for 2-3 hours in the last half of the dark phase.The results suggest that, in rats, voluntary running limited to a fixed time daily alters the pattern of nycthemeral variations in body core temperature and locomotor activity, i.e., body core temperature and running activity increase during the period when the rats were previously allowed to exercise.