Cellular and molecular analysis of cryptic testes in dolphins

在许多哺乳动物中，睾丸位于阴囊中，保持在比深层体温更低的温度。结果，精子发生保持活跃。然而，一些哺乳动物的睾丸，如海豚、大象和鬣狗，存在于腹腔内。目前尚不清楚它们如何在这种情况下保持精子生成。本研究旨在探讨隐匿性睾丸与热休克蛋白和凝集素的出现/消失之间的关系。除了海豚，我们还使用了实验性隐睾鼠、性腺不活跃的仓鼠睾丸和胎儿和出生后早期(精子发生前)的小鼠睾丸。在小鼠实验性隐睾症中，许多变性细胞表现为核浆凝聚。TUNEL阳性细胞较多见。这些数据提供了证据，证明至少有部分细胞死于细胞凋亡。而HSP70.2在粗线期精母细胞…中表达更多的和精子细胞。隐睾腺内未见反应。在仓鼠睾丸中，在暴露于短的一天周期后的13周，精子发生严重中断。扁豆凝集素(DBA)能与精原细胞特异结合。DBA在活动期仅与A型精原细胞结合，而在非活动期则与A型、中间型和B型精原细胞结合。在生前发育过程中，观察到性细胞中sWGA、VVA和LEA凝集素的特征结合模式。这些凝集素可能与性腺细胞的分化有关。在宽吻海豚中，HSP86在B型精原细胞、精母细胞和精子细胞中呈强阳性表达。Hsp84在B型精原细胞中有较强的表达，而在精母细胞和精子细胞中未见反应。在里索海豚中，hsp86在粗线期和细线期前的精母细胞中表达。Hsp84与B型精原细胞呈阳性反应。这些发现表明，每种蛋白质可能在精子发生的不同过程中发挥作用。较少

In many mammals, the testis is located in the scrotum and is maintained cooler than the deep body temperature. As a result, spermatogenesis is retained to be active. However, the testes in some mammals, such as dolphins, elephants and hyraxes, are present within the abdominal cavity. It remains to be unclear how they can maintain their spermatogenesis under this condition. The present study was designed to examine the relationship between the cryptic testis and the appearance/disappearance of heat shock proteins and lectins. In addition to dolphins, we used experimental cryptorchid mice, gonadally inactive hamster testes and mouse testes at fetal and early postnatal stages (prespermatogenesis). In experimental cryptorchidism of mice, many degenerating cells showed condensation of the nucleus and cytoplasm. TUNEL-positive cells were frequently observed. These data provide evidence that at least some of the cells die by apoptosis. While, hsp 70.2 was expressed in pachytene spermatocytes … More and spermatids. No reaction was detected in cryptorchid testes. In hamster testes, spermatogenesis was severely disrupted at 13 weeks after exposure to a short day cycle. Dolichos biflorus (DBA) agglutinin bound specifically to spermatogonia. DBA bound to only type A spermatogonia in active testes, whereas it bound to type A, intermediate and type B spermatogonia in inactive testes. During prespermatogenesis, characteristic binding patterns of sWGA, VVA and LEA agglutinin were observed in gonocytes. These lectins nay be related to the differentiation of gonocytes. In bottlenose dolphins, hsp86 was strongly positive in type B spermatogonia, spermatocytes and spermatids. Hsp84 was strongly expressed in type B spermatogonia, whereas no reaction was detected in spermatocytes and spermatids. In Risso's dolphins, hsp86 was expressed in pachytene and preleptotene spermatocytes. Hsp84 reacted with type B spermatogonia. These findings suggest that each protein may play a role in the different process of spermatogenesis. Less