生后不同发育阶段大鼠睾丸生精小管和间质细胞形态学的变化

目的通过对生后不同年龄SD大鼠睾丸生精小管、间质细胞的组织形态学观察,探讨生后不同发育阶段睾丸生精细胞和间质细胞的发育及变化规律。方法取10天、20天、30天、4月、12月、24月龄雄性大鼠睾丸,常规石蜡包埋、切片、HE染色,镜下观察不同发育阶段生精小管和间质细胞的变化,并进行定量组织学分析。结果⑴生后10天睾丸生精小管细而稀疏,小管中仅见精原细胞和支持细胞,可见单个和成群存在的间质细胞,20天小管中出现初级精母细胞,间质细胞消失,30天龄出现精子细胞,间质细胞再度出现;⑵4月龄生精小管密集、小管外直径和细胞层数均明显增加（P（0.05）并达最大值,上皮内生精活跃,间质内见有大量嗜酸性的间质细胞;⑶12月龄生精细胞层数减少并出现空泡变性,上皮变薄,间质细胞数量减少,体积变小,成纤维细胞增多,界膜增厚;⑷24月龄生精小管明显稀疏,上皮层数降低（P（0.05）,生精细胞和间质细胞均明显减少,内空泡增多,支持细胞也出现空泡变。结论生后10~30天生精小管内尚无精子形成,处于幼年期,除20天龄外,间质内均可见较多的间质细胞;4月龄的青年期生精小管内生精能力和激素分泌能力达高峰,处于生殖旺盛的性成熟阶段;12月龄的中年期睾丸出现衰老性变化，至24月龄老年期生精能力和激素奇泌能力均明显降低.

Research on morphological changes of testicular seminiferous tubules and leydig cells of rats in different development stages

Objective： To research the development and change characteristics SD rat spermatogenic cells and Leydig cells in different development stages through histomorphological observation.Methods： Testes of male rats aged 10days,20days,30days,4months,12months and 24months were removed,embedded routinely in paraffine,sliced up and H-E stained.The seminiferous tubules and Leydig cells in different development stages were observed under microscope and analyzed by the method of quantitative histology.Results： 1.In 10-day-old rats, the seminiferous tubules were slender and sparse with only spermatogunia and supporting cells in them; leydig cells were present singlely or in aggregates. In 20-day-old rats, primary spermatocytes appeared in the seminiferous tubules and Leydig cells disappeared, in 30-day-old rats, spermatids were present in the seminiferous tubules and Leydig cells appeared again. 2. In 4-month-old rats, the seminiferous tubules hecame dense will their outer diameter and the number of their cell layers increasing to the maximum; there was active spermatogenesis in the epithelium and large numbers of eosinophilic Leydig cells in the interstitium. 3. In 12- month-old rats, the number of spermatogenic cell layers decreased accompanied with vacuolation of the cells ; the epithelium became thinner; the Leydig cells decreased both in number and in size, while the fibroblasts increased in number and the limiting menrbranes became thicker. 4. In 24-month-old rats, the seminiferous tubules considerably became sparse, the epithelial layer decreased （ P 〈0.05 ） ; there were more vacuoles in spermatogenic cells and leydig cells, the number of these two types of cells decreasing markedly; vacuolation also place in supporting cells. Conclusion： In juvenile rats （ aged 10-30 days） , there is no spermiogenesis within the seminiferous tubules; in the interstitium are large amounts of leydig cells （absent in rats aged 20 days）, the peaks of spermatogenic and hormone-secreting abilities appeared in puberal