Immunolocalization of inhibin/activin subunits in the Shiba goat fetal, neonatal, and adult testes

The objective of this study was to investigate the cellular immunolocalization of inhibin alpha and inhibin/activin (beta A and beta B) subunits in the fetal, neonatal and adult testes of Shiba goats. The testes were obtained from a fetus at 90 days, a neonate at 15 days, and two adult Shiba goats (both of 3 years old). The sections of testes were immunostained by the avidin-biotin-peroxidase complex method (ABC) using polyclonal antisera raised against porcine inhibin alpha, inhibin/activin beta A, and inhibin/achvin beta B. Inhibin alpha and inhibin/activin (beta A and beta B) subunits were expressed in Leydig cells, but not in the Sertoli cells of the fetus with a weak immunostaining. An increase in the number of positive cells and a more intense immunohistochemical signal for inhibin alpha and inhibin/activin (beta A and beta B) subunits were observed in the Leydig cells of neonatal testes. Moreover, inhibin alpha, beta A, and beta B subunits were expressed in the Sertoli cells and Leydig cells of adult testes, respectively. These results suggest that Shiba goats testes have the ability to synthesize inhibins in the fetus, neonate, and adult, and the cellular localization of inhibin/activin subunits showed age-related changes in fetal, neonatal, and adult testes of Shiba goats.