Morphological and molecular analyses on testiculture tissuer at hibernation period

首先，日本小菊头蝠（冬眠）精子发生的季节性变化进行了研究，通过光学显微镜。3月，曲细精管几乎没有管腔。生精上皮由支持细胞和精原细胞组成。6月曲细精管直径逐渐增大。管腔清晰可见。精母细胞偶尔被识别。在8月和10月，可以清楚地观察到活跃的精子发生。12月（冬眠期）精子发生完全消失。小管直径明显减小。多数生精上皮仅含支持细胞和精原细胞。第二，作为冬眠实验的初步步骤，我们研究了长和短光周期对叙利亚仓鼠睾丸的影响。在长光周期下，精子发生活跃，而在短光周期下，精子发生完全停止。免疫组化检测到Smad2和Smad3， ...更多信息 在活跃睾丸精母细胞的细胞质中。在退化的睾丸中，在精母细胞的核中检测到两种Smads。第三，研究了叙利亚仓鼠在短光照和低环境温度下精子发生的形态学动态。雄性叙利亚仓鼠在长光照条件下，转移到短光照条件下（6L 18D），13周后诱导睾丸退化，然后将部分仓鼠从23℃环境转移到5℃环境（5℃组）。剩余仓鼠继续保持在23℃（23℃组）。23℃组复发迅速。2周时（共15周）粗线期精母细胞出现，4周时检测到圆形精子细胞，8周时精子发生最终恢复。而5℃组在最初几周内几乎没有复发。13周（共26周）时，粗线期精母细胞出现，16周时观察到圆形精子细胞。直到20周才发现精子发生活跃。然后观察5℃和23℃组生精上皮细胞增殖和凋亡活性的变化。5 ℃组与23 ℃组相比，精原细胞增殖活性无明显差异，但凋亡率明显增加。此外，这种增加在冬眠期间更为显著。结果提示，低温可使睾丸复发延迟，这种延迟是由于5℃组精原细胞凋亡活性增加而非增殖活性改变所致。与寒冷环境温度相比，5℃组睾丸复发延迟，这种延迟是由于精原细胞凋亡活性增加而非增殖活性改变所致。与寒冷的环境温度相比，冬眠可能是刺激凋亡活性以诱导复发延迟的更主导因素。少

First, seasonal changes in spermatogenesis of Japanese lesser horseshoe bats (a hibernating) were examined by light microscopy. In march, the seminiferous tubules revealed almost no lumen. The seminiferous epithelium consisted of Sertoli ells and spermatogonia. In june, the seminiferous tubule gradually increased in diameter. Lumen was clearly seen. Spermatocytes were occasionally recognized. In August and October, active spermatogenesis was clearly observed. In December (hibernation period), spermatogenesis completely disappeard. The diameter of tuvules greatly decreased. In most cases, the seminiferous epithelium contained only Sertoli cells and spermatogonia. Second, as the preliminary step for hibernation experiments, we examined the influence of long and short photoperiods in testes of Syrian hamsters. Under a long photoperiod, active spermatogenesis was observed, whereas under a short photoperiod, spermatogenesis completely ceased. Immunohistochemistry detected Smad2 and Smad 3 i … More n the cytoplasm of spermatocytes in the active testes. In the regressed testes, both Smads were detected in the nucleus of spermatocytes. Third, morphological dynamics on spermatogenesis in Syrian hamsters exposed to both short photoperiod and low ambient temperature were examined. Male Syrian hamsters, kept in a long photoperiod, were transferred to a short fff (6L18D) and kept there for 13weeks to induce testicular regression Some hamsters were then transferred from the room at 23℃ to that at 5℃(5℃ group). Remaining hamsters were continuously kept at 23℃ (23℃group). As a result, a rapid recrudescence was observed in 23℃ group. At 2 weeks (total 15 weeks), pachytene spermatocytes appeared, at 4 weeks round spermatids were detected, and at 8 weeks spermatogenesis finally recomvered. While littl recrudescence was observed in 5℃group during the first several weeks. At 13 weeks (total 26 weeks), pachytene spermatocytes appeared and at 16weeks round spermatids were observed. It was not until 20 weeks that active spermatogenesis was recognized. Then, the changes in the proliferative and apoptotic activities in the seminiferous epithelium of 5℃ and 23℃ groups were examined. Although no significant difference in spermatogonia proliferative activity between 5℃ and 23℃ groups was confirmed, a notable increase in the rate of apoptosis was observed in 5℃ group compared with 23℃ group. Furthermore, this increase was more salient during the hibernation period. These findings suggest that cold ambient temperature causes the delay of testicular recrudescence and this delay arises from the increase of apoptotic activity but not the change in proliferative activity in spermatogonia in 5℃ group. Compared to cold ambient temperature causes the delya of testicular recrudescence and this delay arises from the increase of apoptotic activity but not the change in proliferative activity in spermatogonia in 5℃ group. Compared to cold ambient temperature, hibernation may be more dominant factor that stimulates the apoptotic activity to induce a recrudescent delay. Less