Powers J B, Jetton A E, Wade G N
Department of Psychology, University of Massachusetts, Amherst 01003-7710.
Am J Physiol. 1994 Jul;267(1 Pt 2):R185-90. doi: 10.1152/ajpregu.1994.267.1.R185.
Two experiments evaluated the combined effects of food deprivation and runningwheel access on estrous cycles and estrous behavior of female hamsters. In experiment 1, food deprivation on days 1 and 2 of the estrous cycle disrupted the next expected ovulation, and this effect was more, rather than less, robust in females allowed to exercise in running wheels while they were deprived. In experiment 2, a similar protocol was used except the females were ovariectomized and received sequential injections of estradiol benzoate (EB; 5 micrograms) and progesterone (P; 200 micrograms) separated by 48 h to induce lordosis, which was tested 4-5 after P. Food deprivation concomitant with hormonal treatment diminished lordosis durations, but this effect was significant only among the females that were permitted to run in activity wheels. Previous findings demonstrated that access to running wheels attenuated the inhibitory effects of short photoperiod exposure on hamster estrous cycles. In contrast, the present results indicate that this same manipulation exaggerates rather than diminishes the inhibitory effects of food deprivation on estrous cycles and hormone-induced behavioral estrus.
两项实验评估了食物剥夺和使用跑轮对雌性仓鼠发情周期及发情行为的综合影响。在实验1中，发情周期第1天和第2天的食物剥夺扰乱了下一次预期的排卵，并且在剥夺食物期间允许在跑轮上运动的雌性中，这种影响更为强烈而非减弱。在实验2中，采用了类似的方案，只是雌性仓鼠被切除卵巢，并在48小时的间隔内依次注射苯甲酸雌二醇（EB；5微克）和孕酮（P；200微克）以诱导脊柱前凸，在注射P后4至5天进行测试。与激素处理同时进行的食物剥夺缩短了脊柱前凸持续时间，但这种影响仅在被允许在活动轮上跑动的雌性中显著。先前的研究结果表明，使用跑轮减弱了短光照周期暴露对仓鼠发情周期的抑制作用。相比之下，目前的结果表明，同样的操作会夸大而非减弱食物剥夺对发情周期和激素诱导的行为性发情的抑制作用。
