藏绵羊羔羊睾丸leydig细胞增龄性变化特征

Structure characteristics of leydig cell in Tibetan sheep lamb at different ages

为了比较分析不同月龄藏绵羊羔羊睾丸leydig细胞发育特征，探索其发育特征与生精功能的关系．应用组织化学方法及电子显微镜技术，研究了1～6月龄羔羊睾丸leydig细胞增龄性变化特征．光镜观察结果表明：leydig细胞及其周围间质组织结构随月龄增龄性变化明显．1，2月龄羔羊睾丸间质内毛细血管分布较少，管壁内皮细胞较圆，发育不完善，周围有散在的纺锤形或星形的幼稚成纤维细胞，结缔组织分布较少；3，4月龄羔羊睾丸间质内血管内皮细胞发育完善，巨噬细胞位于间质血管周围，细胞较大，形态不规则，结缔组织有所增加；5，6月龄羔羊睾丸间质内毛细血管数量增多，管壁内皮细胞包围成形，成纤维细胞呈长索状，轮廓清楚，核仁大而明显，结缔组织明显增加．电镜下观察结果表明，3月龄之前睾丸leydig细胞以幼稚型为主，核较圆，异染色质较多，胞体近卵圆形；3月龄的羔羊睾丸leydig细胞体积明显增大，可见少量粗面内质网，胞浆内有少量分泌性颗粒出现．4月龄及以后的羔羊leydig细胞体积大，胞核多不规则，核仁明显，胞浆内空泡及分泌性颗粒明显增多；间质成纤维细胞呈长索状，血管壁内皮细胞包围成形．因此，3月龄之前，藏绵羊羔羊leydig细胞处于胚胎型向成熟型过渡时期；4月龄以后逐渐发育成熟，为leydig细胞的局部分泌调节提供结构支持，对生精小管的进一步发育以及后期精子发生具有重要意义．

This experiment was conducted to investigate the structure characteristics of the Tibetan sheep lamb＇s leydig cells at different months. This study uses histochemistry and transmission electron mi- croscope methods to characterize the microstructure and ultrastructure of the leydig cells in Tibetan sheep lamb＇s testis. The observations made with the light microscope were obvious morphological changes at different ages,the leydig cells were scattered in the interstitial connective tissue which were abundant with collagen between the seminiferous tubules, its development were inmature before 3-month-old and the numbers were increasing;although, the macrophages shaped irregularly were located near the interstitial blood vessel with the interstitial vascular endothelial cells were developed enough at 3-4 month old, after that, the lipid droplets in Leydig cells were appeared occasionally, the volume of leydig cells were not changed but interstitial tissues has further increased and abundant with collagen. The electron microscopic studies show that the leydig cells were oval with round shaped nuclei and many heterochromatin before 3-month- old, but the cell＇s volume changed more largely just development over 3-month old and appeared few secre- tory granules. In 4 month growth, the Leydig cells were irregularly shaped nuclei with prominent nucleoli, the vacuoles and secretory granules were present obviously,interstitial fibroblasts were long in shape and the blood vessels wall were surrounded by endothelial cells. Taken together, the leydig cells in the Tibetan sheep lamb＇s were in the transition period which developed from embryonal type to a mature stage before 3 months;but became gradually mature after that,the study providing the structural support for the local se- cretion of leydig cells,it is very important for the further development of seminiferous tubule and the late spermatogenesis.