大鼠卵巢的生后发育

Postnatal Development of the Rat Ovary

目的研究大鼠卵巢中卵泡生长发育的增龄性变化,为生殖生物学研究寻找动物模型。方法用组织学方法,观察了0天～15月大鼠卵巢的形态结构。结果0天见卵母细胞聚集呈团索状,未见卵泡;4天见大量原始卵泡;1周出现大量初级卵泡;2周见次级卵泡;3周次级卵泡数量增加,卵泡腔扩大;1月可见不同发育阶段的卵泡和闭锁卵泡;45天出现黄体;2月～5月,有大量黄体和生长卵泡;6月～8月,卵巢体积缩小,卵泡数量减少;12月萎缩,未见正常卵泡和黄体;15月,纤维化,可见囊泡。结论大鼠从6月开始,生殖功能随月龄增长而进行性衰减,机体逐渐衰老。大鼠可用作研究女性生殖与衰老关系的动物模型。

Objective To investigate the age-related changes of follicle development in the ovary and to look for an animal model for the study of reproductive biology. Methods The morphological structure of 0 day-old to 15 month-old rat ovaries were histologically examined. Results When the rat is 0 days old, oocytes in the ovary were arranged in a cord-like cluster and follicles were absent. After 4 days primordial follicles filled all the regions of the ovary. Numerous primary follicles appeared at 1 week. Secondary follicles were developed from 2 weeks. At 3 weeks the number of secondary follicles increased and their follicular cavity enlarged. At 1 month follicles in various stages of development and atretic follicles were seen. Corpora lutea were present at 45 days. A large population of corpora lutea and growing follicles were observed from the 2nd month to the 5th month. At 6 to 8 months ovaries decreased in size and follicles diminished in number. No healthy follicles and corpora lutea were found in 12-month old ovaries which were atrophic. At 15 months ovaries showed fibrosis and some cysts completely devoid of follicular cells were observed in them. Conclusion From 6 months on the reproductive function of female rats declines progressively with increasing age （ month ） and their organsenesces gradually. Female rats can be used as animal models to study the relationship between female reproduction and ageing.