Spearow J L
Biol Reprod. 1986 Dec;35(5):1175-86. doi: 10.1095/biolreprod35.5.1175.
The present study examined a randomly selected control line (C) and a large litter size-selected line of mice (S1) to determine changes in the kinetics of follicular growth that have occurred in response to selection for large litter size. For each follicle type (FT), the number of healthy and atretic follicles, length of components of granulosa cell cycle, follicular growth rate, and follicular flux were determined microscopically from serially sectioned ovaries of Lines C and S1 mice. Selection for litter size significantly increased the number of small and medium, and some large follicle-size classes. While selection for litter size did not change the overall incidence of atresia at proestrus, it did decrease the incidence of atresia in the large Type 7 follicles by 19%. Selection for litter size also increased ovarian weight at proestrus. Selection for litter size increased the rate of growth through FT 3a, 5a, and 5b, and reduced the time required for follicles to grow from primordial to Graafian follicles from 39.1 days in Line C to 33.4 days in Line S1. Selection for large litter size also increased the flux of follicles through follicle Types 3a to 5b by 72%, and through follicle Types 6 and 7 by 21%. Genetic variation was found in many aspects of the kinetics of follicular growth.
本研究检测了一条随机选择的对照品系（C）和一个经多胎选育的小鼠品系（S1），以确定因多胎选育而发生的卵泡生长动力学变化。对于每种卵泡类型（FT），从C系和S1系小鼠卵巢的连续切片中，通过显微镜确定健康卵泡和闭锁卵泡的数量、颗粒细胞周期各组分的长度、卵泡生长速率和卵泡通量。多胎选育显著增加了中小卵泡以及部分大卵泡类别的数量。虽然多胎选育并未改变动情前期闭锁的总体发生率，但它确实使7型大卵泡的闭锁发生率降低了19%。多胎选育还增加了动情前期的卵巢重量。多胎选育提高了通过3a、5a和5b型卵泡的生长速率，并将卵泡从原始卵泡生长到格拉夫卵泡所需的时间从C系的39.1天缩短至S1系的33.4天。多胎选育还使通过3a至5b型卵泡的卵泡通量增加了72%，通过6型和7型卵泡的卵泡通量增加了21%。在卵泡生长动力学的许多方面都发现了遗传变异。
