engleski

Expression of inhibin in fetal and adult human testis

Aim Inhibin is known to influence the secretion of FSH from the adenohypophysis. Therefore, it is one of the key regulators of spermatogenesis. Whereas there are some data on the expression of inhibin in the adult testis, there is a lack of data on the developing fetal human testis. The aim of our study was to identify cells that express inhibin in the fetal and adult human testis. In addition, we wanted to compare findings in the mentioned (fetal and adult) tissue samples. Materials and methods Biopsies of adult human testis were obtained form 8 patients with the vasectomy reversal. 22 samples of fetal human testes at various gestational age (16-38 weeks of gestation) were obtained from miscarried children during the routine paedopathological section. After dissection, small tissue samples were immediately fixed in Bouin’ s fluid, dehydrated and embedded in paraffin. Paraffin sections were made by means of rotary microtome (Leica). For immunohistochemstry (IHC), a primary antibody to inhibin (Biogenex, San Ramon) followed by an appropriate IHC kit (EnVision, Dako, Glostrup) was applied. Results Testicular biopsies from vasectomy patients demonstrated a regular spermatogenesis and morphology of the interstitial testicular tissue. Fetal human testis consisted of sex cords and interstitial tissue bearing testosterone producing Leydig cells. Sex cords were lined with Sertoli cells and prospermatogonia. IHC indicated a strong expression of inhibin within the cytoplasm of Sertoli cells. In the testicular interstitial compartment, some Leydig cells were also positive to inhibin. As for the human fetal testis, two cell types were positive during the followed gestational age (16-38 weeks of gestation): fetal Sertoli cells and some Leydig cells. Conclusion On the basis of IHC data, the expression of inhibin could be recorded at early stages of the human fetal testis development. There is a significant overlapping in the expression of the inhibin in the fetal and adult human testicular tissue. All Sertoli cells were positive to inhibin (in the both adult and fetal samples) whereas a number of Leydig cells (but not all of them) expressed inhibin.

inhibin; testis; immunohistochemistry

nije evidentirano