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The expression of inducible nitric oxide synthase (iNOS) in the testis and epididymis of rats with a dihydrotestosterone (DHT) deficiency


In our previous studies, we showed that a finasteride-induced DHT deficiency may cause changes in the morphology of the seminiferous epithelium without any morphological alteration of the epididymis. In this study, we demonstrated the constitutive immunoexpression of inducible nitric oxide synthase (iNOS) in the testis and epididymis of Wistar rats treated with finasteride for 28 days (the duration of two cycles of the seminiferous epithelium) and 56 days (the duration of one spermatogenesis). We noted that a 56-day finasteride treatment mainly caused a decrease in the level of circulating DHT, as well as a statistically insignificant decrease in the level of T. The hormone deficiency also led to a change in the iNOS immnoexpression in the testis and epididymis of the finasteride-treated rats. In vitro, DHT did not modify NO production by the epithelial cells of the caput epididymis even when stimulated with LPS and IFNγ, but it did give rise to an increase in NO production by the epithelial cells of the cauda epididymis without the stimulation. DHT did not have a statistically significant influence on estradiol production by cultured, LPS- and IFNγ-stimulated epithelial cells from the caput and cauda epididymis. In conclusion, our data clearly indicates that a finasterideinduced DHT deficiency intensifies the constitutive expression of iNOS in most rat testicular and epididymal cells, so it can be expected that the expression of inducible nitric oxide synthase (iNOS) could be regulated by DHT. On the other hand, the profile of the circulating DHT and T levels strongly suggests that the regulation of constitutive iNOS expression is complex and needs more detailed study.





5α-reductase type 1


5α-reductase type 2


androgen receptor



E2 :



enzyme linked fluorescent assay


estrogen receptor α


estrogen receptor β


interferon gamma


Leydig cell




nitric oxide

NO2− :



nitric oxide synthase


endothelial nitric oxide synthase


inducible nitric oxide synthase


neuronal nitric oxide synthase


pachytene spermatocyte


preleptotene spermatocyte




reverse transcriptase-polymerase chain reaction


Sertoli cell








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Correspondence to Agnieszka Kolasa or Barbara Wiszniewska.

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Kolasa, A., Marchlewicz, M., Kurzawa, R. et al. The expression of inducible nitric oxide synthase (iNOS) in the testis and epididymis of rats with a dihydrotestosterone (DHT) deficiency. Cell Mol Biol Lett 14, 511–527 (2009).

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Key words

  • iNOS immunoexpression
  • DHT-deficiency
  • Testis
  • Epididymis
  • Rat