Concentrations of Immunoreactive Inhibin in Seminal Plasma and Serum from Normospermic, Oligospermic, Vasectomized, Klinefelter's Syndrome, and Sertoli-cell—only Syndrome Subjects

¹ Department of Obstetrics and Gynecology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas
² Institute for Research in Reproduction (Indian Council of Medical Research), Parel, Bombay, India

Semen samples and blood were collected from 57 men: 23 normospermic, 20 oligospermic, 10 vasectomized, two with Klinefelter's syndrome, and two with Sertoli-cell—only syndrome. Inhibin was measured by radioimmunoassay techniques as reported previously. Immunoreactive inhibin concentrations in seminal plasma were found to be 8000 to 10,000 times higher than in blood. A significant correlation (P < 0.005) was observed between the serum and seminal plasma concentrations in all groups. No direct correlation was observed between immunoreactive inhibin concentrations in serum or semen with number of sperm in the ejaculate or with sperm motility. Seminal plasma and serum immunoreactive inhibin levels in normospermic subjects were significantly higher than in oligospermic, vasectomized, and Klinefelter's syndrome subjects (P < 0.001 and < 0.01, respectively).

     Key words: inhibin, radioimmunoassay, seminal plasma, serum

Submitted on April 8, 1980
Revised on May 20, 1980
Accepted on June 11, 1980