Asai Sayaka, Ohta Ryo, Shirota Mariko, Sato Masako, Watanabe Gen, Taya Kazuyoshi
United Graduate School of Veterinary Sciences, Gifu University, Japan.
Endocrine. 2002 Jul;18(2):161-6. doi: 10.1385/ENDO:18:2:161.
The high- and low-avoidance animals (HAA and LAA rats) were originally selected from Sprague-Dawley rats for their shuttle-box task. Reproductive endocrinology during the estrous cycle was compared between HAA and LAA rats. All HAA rats showed a regular 4-d estrous cycle, whereas most LAA rats (70.8%) showed a regular 5-d estrous cycle. The peak level of preovulatory luteinizing hormone (LH) surge level was significantly lower in LAA rats than in HAA rats on the day of proestrus. In contrast, the peak level of prolactin surge on the day of proestrus was significantly higher in LAA rats than in HAA rats. Plasma concentrations of follicle-stimulating hormone (FSH) and estradiol-17beta were significantly lower in LAA rats as compared with HAA rats at 12 h on the day of estrus and from 24 h on the day of diestrus to 18 h on the day of proestrus. On the other hand, plasma concentrations of progesterone were significantly higher in LAA rats compared with HAA rats on the day of diestrus. The number of antral follicles (300-600 microm in diameter) at 12 h on the day of proestrus was significantly fewer in LAA rats than in HAA rats. The size and number of corpus luteum at 12 h on the day of estrus were significantly greater in LAA rats than in HAA rats. These results clearly demonstrated that apparent differences are observed in reproductive endocrinology between two Hatano strains. These strain differences probably originated from neural regulation of pituitary hormones.
高回避和低回避动物（高回避和低回避大鼠）最初是从斯普拉格-道利大鼠中根据其穿梭箱任务挑选出来的。对高回避和低回避大鼠发情周期中的生殖内分泌进行了比较。所有高回避大鼠都表现出规律的4天发情周期，而大多数低回避大鼠（70.8%）表现出规律的5天发情周期。在发情前期，低回避大鼠排卵前促黄体生成素（LH）峰值水平显著低于高回避大鼠。相反，在发情前期，低回避大鼠催乳素峰值水平显著高于高回避大鼠。在发情日12小时以及在动情后期24小时至发情前期18小时期间，低回避大鼠血浆中促卵泡生成素（FSH）和雌二醇-17β的浓度显著低于高回避大鼠。另一方面，在动情后期，低回避大鼠血浆孕酮浓度显著高于高回避大鼠。在发情前期12小时，低回避大鼠直径为300 - 600微米的窦卵泡数量显著少于高回避大鼠。在发情日12小时，低回避大鼠黄体的大小和数量显著大于高回避大鼠。这些结果清楚地表明，在两个羽田品系之间的生殖内分泌方面观察到了明显差异。这些品系差异可能源于垂体激素的神经调节。
