Fujisawa M, Hayashi A, Okada H, Arakawa S, Kamidono S
Department of Urology, Kobe University School of Medicine, Japan.
Eur Urol. 1997;31(2):237-42. doi: 10.1159/000474457.
Temperature is considered to be an important local regulating factor of testicular function. We investigated whether a high temperature would affect the activity of DNA polymerases alpha, beta, and gamma (EC2.7.7.7) and DNA topoisomerase I in the testes which are required for germ cell differentiation.
An in vitro rat testis tissue culture system was used to evaluate the activity of DNA polymerases alpha, beta, and gamma and DNA topoisomerase I after incubation at 31 and 37 degrees C. The expression of proliferating cell nuclear antigen was evaluated immunohistochemically in the testis.
Incubation at 37 degrees C significantly reduced the activity of all four enzymes as compared with incubation at 31 degrees C. Reducing the temperature to 31 degrees C after prior incubation at 37 degrees C partially restored DNA polymerase alpha activity. Expression of proliferating cell nuclear antigen demonstrated a reduction in DNA synthesis in the seminiferous tubules after incubation at 37 degrees C CONCLUSION: These findings indicate that a high temperature of 37 degrees C reduces the activity of the enzymes involved in the testicular synthesis of DNA which may cause the impairment of spermatogenesis.
温度被认为是睾丸功能的一个重要局部调节因素。我们研究了高温是否会影响生殖细胞分化所需的睾丸中DNA聚合酶α、β和γ（EC2.7.7.7）以及DNA拓扑异构酶I的活性。
使用体外大鼠睾丸组织培养系统，评估在31℃和37℃孵育后DNA聚合酶α、β和γ以及DNA拓扑异构酶I的活性。通过免疫组织化学方法评估睾丸中增殖细胞核抗原的表达。
与在31℃孵育相比，在37℃孵育显著降低了所有四种酶的活性。在37℃预先孵育后将温度降至31℃可部分恢复DNA聚合酶α的活性。增殖细胞核抗原的表达表明在37℃孵育后曲细精管中的DNA合成减少。结论：这些发现表明37℃的高温会降低睾丸DNA合成中所涉及酶的活性，这可能会导致精子发生受损。
