Le Moëne Olivia, Hernández-Arteaga Enrique, Chu Xi, Ågmo Anders
Department of Psychology, University of Tromsø, Huginbakken 32, 9037, Tromsø, Norway.
Laboratorio de Neurofisiología de la Conducta Reproductiva, Instituto de Neurociencias, CUCBA, Universidad de Guadalajara, Guadalajara, Mexico.
Behav Processes. 2020 May;174:104101. doi: 10.1016/j.beproc.2020.104101. Epub 2020 Feb 28.
Gonadally intact female rats display sexual behaviors only during a portion of the estrus cycle. In standard experimental setups, the on- and offset of sexual behavior is gradual. However, in naturalistic settings, it is almost instantaneous. We assessed the changes in sociosexual behaviors at the beginning and end of behavioral estrus in ovariectomized females treated with ovarian hormones. Rats were housed in a seminatural environment, in groups of three males and four females. We scored female and male behavior during the 8 min preceding and following the first and last lordosis of behavioral estrus. Immediately before the first lordosis, there was a sharp increase in female paracopulatory behaviors whereas the end of estrus was marked by a sudden decrease in these behaviors. There was no systematic change in other female behavior patterns. These data suggest that the display of female paracopulatory behaviors plays a key role. Both during transition into and out of behavioral estrus, most behavioral changes occurred within one minute. The rapid changes must be unrelated to ovarian hormone fluctuations in these ovariectomized females. Perhaps they can be explained in terms of hormone-induced, dynamic (chaotic) changes in the function of critical structures within the brain.
性腺未受损的雌性大鼠仅在发情周期的一部分时间内表现出性行为。在标准实验设置中，性行为的开始和结束是渐进的。然而，在自然环境中，性行为几乎是瞬间发生的。我们评估了用卵巢激素治疗的去卵巢雌性大鼠在行为发情开始和结束时社会性行为的变化。大鼠被饲养在半自然环境中，每组三只雄性和四只雌性。我们对行为发情的第一次和最后一次脊柱前凸之前和之后的8分钟内雌性和雄性的行为进行了评分。就在第一次脊柱前凸之前，雌性副交配行为急剧增加，而发情结束时这些行为突然减少。其他雌性行为模式没有系统性变化。这些数据表明，雌性副交配行为的表现起着关键作用。在进入和退出行为发情期间，大多数行为变化都发生在一分钟内。这些去卵巢雌性大鼠的快速变化肯定与卵巢激素波动无关。也许可以用激素诱导的大脑关键结构功能的动态（混沌）变化来解释它们。
