Stefanick M L
Physiol Behav. 1983 Dec;31(6):737-43. doi: 10.1016/0031-9384(83)90268-8.
Spontaneous seminal emission (SSE) by sexually naive and experienced rats occurred almost exclusively in the light period of a 14:10 LD cycle. The circadian pattern of SSE slowly shifted following an LD reversal and was completely reversed by three weeks. The diurnal variation in parameters of sexual activity which are associated with sexual arousal shifted much more readily such that it was reversed within one week of the LD reversal. In contract, parameters of sexual behavior which are associated with the ejaculatory mechanism were altered following the LD shift with a phase-shifting pattern more similar to that exhibited for SSE, such that the diurnal variation seen before the LD shift was not reestablished until the third week after the shift. The characteristic pattern of SSE in 14:10 LD lighting was disrupted with two weeks of a shift to constant illumination, but the number and weight of spontaneously produced plugs did not change. Finally, there were no differences in any component of the display of penile reflexes by 29 rats tested in the dark period compared to 19 rats tested in the light period, despite significant circadian variation in the copulatory activity of these animals.
性经验缺乏和有性经验的大鼠的自发性射精（SSE）几乎只发生在14:10光照-黑暗周期的光照期。在光照-黑暗周期颠倒后，SSE的昼夜节律模式缓慢转变，并在三周内完全逆转。与性唤起相关的性活动参数的昼夜变化更容易转变，以至于在光照-黑暗周期颠倒后的一周内就发生了逆转。相比之下，与射精机制相关的性行为参数在光照-黑暗周期转变后发生了改变，其相移模式更类似于SSE所表现出的模式，以至于在光照-黑暗周期转变前看到的昼夜变化直到转变后第三周才重新建立。在14:10光照-黑暗光照条件下SSE的特征模式在转变为持续光照两周后被打乱，但自发产生的栓塞的数量和重量没有变化。最后，在黑暗期测试的29只大鼠与在光照期测试的19只大鼠相比，阴茎反射表现的任何组成部分都没有差异，尽管这些动物的交配活动存在显著的昼夜变化。
