Expression of inhibin B betaB subunits in the testicular tissues of azoospermia patients with different pathological alterations

Objective:To investigate the expression of inhibin B βB subunits in human testicular tissues.Methods:Eighty-three cases of the azoospermia underwent testicular biopsy.In accordance with the pathological alterations of spermatogenesis,the samples were divided into four groups:Sertoli-cell-only syndrome(n=21);hypospermatogenesis(n=20),maturation arrest(n=24)and almost normal spermatogenesis(n=18).Immunohistochemical staining for inhibin B βB subunits was conducted on the paraffin-embedded sections of different spermatogenesis to localize inhibin B βB subunits in the seminiferous tubules.Results:Immunohistochemically,positive products of inhibin B βB subunits were found in both the seminiferous tubules and interstitial tissues of the testis as brown or yellow particles in the cytoplasm.Leydig cells and early intermediate spermatogenic cells showed a very strong positivity;Sertoli cells in the seminiferous tubules were mostly positive;peritubular myoid cells showed a weak positive staining;but no positive expression of inhibin B βB subunits was found in late spermatids and mature sperm.Conclusion:Inhibin B may be produced by both Sertoli cells and early spermatogenic cells in the seminiferous tubules.