Morphological and molecular analyses on testiculture tissuer at hibernation period

首先，用光学显微镜观察了日本小马蹄蝠(冬眠)精子发生的季节变化。今年3月，生精小管几乎没有管腔。生精上皮由支持细胞和精原细胞组成。6月，生精小管直径逐渐增大。流明清晰可见。有时也能识别出精母细胞。8月和10月，精子发生明显活跃。在12月份(冬眠期)，精子发生完全消失。肾小管直径明显减小。在大多数情况下，生精上皮仅含有支持细胞和精原细胞。其次，作为冬眠实验的初步步骤，我们检测了长光周期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。免疫组织化学检测Smad2和Smad3 I…活动期睾丸精母细胞胞浆内较多。在退化的睾丸中，Smad和Smad均位于精母细胞的胞核中。第三，研究了短光周期和低温条件下叙利亚仓鼠精子发生的形态动力学。将雄性叙利亚仓鼠置于长光照条件下，置于6L18D短光照室内，放置13周，诱导睾丸退行性变。23℃时，将部分仓鼠从室内移至5℃(5℃组)。其余仓鼠持续饲养于23℃(23℃组)。结果：23例℃患者均出现快速复发。第2周(共15周)出现粗线型精母细胞，第4周出现圆形精子细胞，第8周恢复生精。而5℃组在最初的几周内几乎没有复发。13周龄(共26周)出现粗线型精母细胞，16周龄可见圆形精母细胞。直到20周，活跃的精子发生才被发现。观察5个℃组和23个℃组生精上皮细胞增殖和凋亡活性的变化。尽管5℃组和23℃组的精原细胞增殖活性无显著差异，但5℃组的凋亡率明显高于23℃组。此外，这种增加在冬眠期间更为显著。这些结果提示，环境温度过低会导致睾丸复燃的延迟，这种延迟是由于5℃组精原细胞的凋亡活性增加而不是增殖活性的改变所致。与低温相比，环境温度导致睾丸复燃延迟，这种延迟是由于5℃组精原细胞的凋亡活性增加，而不是增殖活性的改变。与寒冷的环境温度相比，冬眠可能是更主要的因素，刺激了细胞的凋亡活性，从而导致复发延迟。较少

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