Research Information System
JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION, vol.101, no.1, pp.71-76, 2009 (SCI-Expanded)
In clinical practice, the human chorionic gonadotrophin (hCG) stimulation test is widely used to evaluate testicular function. Inhibin B, a gonadal peptide regulating follice-stimulating hormone (FSH) secretion, is an established marker of Sertoli cell function and spermatogenesis in adults. The aim of this study was to determine whether basal inhibin B levels are able to predict testosterone response to hCG in idiopathic hypogonadotropic hypogonadism (IHH) patients and to evaluate the correlation between inhibin B and gonadotropins in these patients and controls. Inhibin B (n = 15) and other hormones (n = 29) were measured in 29 patients with IHH and 32 controls. Inhibin B (n = 8) and testosterone levels (n = 25) before and after hCG stimulation were measured in 25 male patients with IHH by an immunoassay specific for inhibin B. Basal inhibin B was compared to the testosterone increase after hCG. There was a significant increase in inhibin B (22.6 +/- 9.8 vs 45.07 +/- 13 pg/mL; p =.005), free testosterone (2.92 +/- 0.55 vs 7.9 +/- 1.5 pg/mL; p =.002), and total testosterone (69.0 +/- 15.9 vs 184.9 +/- 44.1 ng/ml; p =.013) levels 72 hours after hCG injection. Inhibin B and the hCG-induced free testosterone and total testosterone increment correlated strongly (r = 0.802, P <.001; r = 0.793, P <.001, respectively).