| Spermatogonial stem cells (SSCs) are the only adult stem cells which cantransfer genetic information into offspring naturally. They can maintain thecontinuous spermatogenesis in male life by self-renewal and differentiation. As themolecular base of tight junction, Connexin (Cx) is expressed widely in variedmammalian tissues and cells. Among this family, Cx43is the most importantmolecule. It has been reported that Cx43played a critical role in cell proliferation andmigration. This study was aimed to investigate the expression of Cx43in the maincomponent of SSCs niches, Sertoli cells, and its effects on SSCs self-renewal anddifferentiation.In the present study, mouse models including Sertoli cell-over proliferation (bypropylthiouracil-treatment, PTU-treatment), busulfan-treatment and unilateralcryptorchidism, were established.5-ethynyl-2-deoxyuridine （EdU） labeling,immunofluorescent histochemistry and hematoxylin-eosin (HE) staining were used toexamine the relationship between the expression of Cx43in SSCs niches and SSCsdevelopment.PTU can lead to the over proliferation of Sertoli cells by inhibit deiodination oftetraiodothyronine. The results show that there was more promyelocytic leukemia zincfinger protein (PLZF) positive spermatogonia in PTU-treated group than that incontrol group on the same time point,which the differences were highly significant(p<0.01) on day10,20and30. Besides, the areas of proliferating cells and expressionof Cx43in PTU group were lower than that in control group.In the busulfan treatment, spermatogonia decreased dramatically.The number ofspermatogonia decreased to the bottom on day8and then recovered gradually. Theoptical density analysis of EdU positive proliferating cells in busulfan-treated mice showed the consistent results, which was declined and then recovered, and the area ofEdU positive cells in experimental group reached the bottom on day5. The expressiontrend of Cx43in busulfan-treated mice was completely on the contrary. Its expressionwent up during the period of day0to day8and then recover to normal. Statisticanalysis indicated that the expressions of Cx43on day3,5,8,10and18weresignificantly higher than that on day0(P<0.01).Artificial unilateral cryptorchidism model can be used to imitate clinicalcryptorchidism.The results show that the size and weight of cryptorchism testisdecreased significantly and the seminiferous epithelia withered evidently, comparedwith the contralateral normal testis. No obvious changes of the numbers of PLZFpositive spermatogonia occurred on day6and12after surgery, while significantlyhigher on day18than contralateral control. The analysis of EdU optical density incryptorchism testis showed no evident changes compared with control on day6and12, while decreased significantly on day18after surgery. However, no significantchanges were observed of the expression of Cx43in cryptorchidism testes aftersurgery. |
PDF Full Text Request