Johnson L, Matt K S, Bartke A, Nguyen H B, Le H T
Department of Veterinary Anatomy, College of Veterinary Medicine, Texas A&M University, College Station 77843-4458.
Biol Reprod. 1987 Oct;37(3):727-38. doi: 10.1095/biolreprod37.3.727.
The number of Leydig cells was determined by stereologic procedures in adult Syrian hamsters housed in long days (14L:10D) to maintain testicular activity (active), in short days (5L:19D) for 12-13 wk to induce testicular regression (photoperiod-induced regressed), or in short days for a period of 21 wk or more to allow spontaneous gonadal recrudescence (spontaneously recrudesced). Testes were removed, sliced, fixed, embedded in Epon 812, and observed by bright-field microscopy. Testicular and seminal vesicle weights, plasma testosterone concentration, total Leydig cell volume per testis, and volume of single Leydig cell were greater (p less than 0.01) in active and recrudesced animals than in regressed animals. The density of Leydig cells was greater in the regressed testes, but the total number per testis was not influenced by photoperiod. In Experiment 2, the rate of recruitment of Leydig cells was determined in 5 adult hamsters exposed to long days (active) or 5 hamsters whose testes were regressed by exposure of animals to short days for 13 wk followed by long-day exposure to initiate testicular growth (photoperiod-induced recrudescing). Hamsters were injected for 3 days/wk for 3 wk with tritiated thymidine, 0.5 or 1 microCi/g body weight. Testes were fixed and tissues prepared, as above, and processed for autoradiography. Again, the photoperiod did not influence the number of Leydig cells per testis. Labeling of Leydig cell nuclei revealed that recruitment of new Leydig cells occurred at approximately 1.3% per day in recrudescing testes but also occurred at approximately 0.6% per day in active testes. Without change in the total number of Leydig cells, new Leydig cells were added continually to the existing population in adult hamsters with either recrudescing or active testes.
通过体视学方法确定成年叙利亚仓鼠的睾丸间质细胞数量。这些仓鼠分别饲养在长日照（14小时光照：10小时黑暗）以维持睾丸活动（活跃状态）、短日照（5小时光照：19小时黑暗）12 - 13周以诱导睾丸退化（光周期诱导退化）或短日照21周或更长时间以实现自发的性腺再发育（自发再发育）。取出睾丸，切片，固定，包埋在Epon 812中，然后通过明场显微镜观察。活跃和再发育动物的睾丸和精囊重量、血浆睾酮浓度、每个睾丸的睾丸间质细胞总体积以及单个睾丸间质细胞体积均大于退化动物（p < 0.01）。退化睾丸中的睾丸间质细胞密度更高，但每个睾丸的总数不受光周期影响。在实验2中，在5只处于长日照（活跃）的成年仓鼠或5只睾丸因短日照暴露13周而退化随后接受长日照暴露以启动睾丸生长（光周期诱导再发育）的仓鼠中，确定睾丸间质细胞的补充率。仓鼠每周注射3天，共注射3周，注射剂量为每克体重0.5或1微居里的氚标记胸腺嘧啶核苷。如上述方法固定睾丸并制备组织，然后进行放射自显影处理。同样，光周期不影响每个睾丸的睾丸间质细胞数量。睾丸间质细胞核的标记显示，再发育睾丸中每天约有1.3%的新睾丸间质细胞生成，而活跃睾丸中每天约有0.6%的新细胞生成。在成年仓鼠中，无论睾丸处于再发育还是活跃状态，在睾丸间质细胞总数不变的情况下，新的睾丸间质细胞不断添加到现有的细胞群体中。
