Immunohistochemical localization of transforming growth factor beta 2 and gene expression using real-time pcr in capsaicin-administered rat testis during puberty

Abstract

The objective of this study was to investigate the effects of capsaicin on the testis distribution of transforming growth factor beta 2 (TGFβ2) and gene expression using real-time PCR in pubescent rats. In this study, rats were divided into 3 groups: capsaicin (CAP), sham, and control. The CAP group was injected with 1 mg/kg doses of capsaicin (10% ethanol and 1% Tween in an 80% distilled water mixture) subcutaneously every day for a period of 1 week. The sham group was injected with a solution of 10% ethanol and 1% Tween in a mixture of 80% distilled water and nothing was injected in control rats. Regarding the histological appearance of testicular sections, the sham and control groups maintained the structure of connective tissue and seminiferous tubule, while in the CAP group, gaps among the tubule cells, invagination in the tubule cell wall, tubular integrity degradation, and breakdowns in the connective tissue were also observed. TGFβ2 immunoreactivity was observed in mature spermatids of all groups; moreover, immunoreactivities in the groups were similar in intensity. These results demonstrate that capsaicin, which is already known to affect gastrointestinal, cardiovascular, and respiratory systems, also interferes with the expression of TGFβ2 in rat testis.