Inhibin is a glycoprotein hormone that is produced from Sertoli cells (in the seminiferous tubules) of the testis. It has a positive action on the spermatogenesis and it inhibits the secretion of FSH from the pituitary
Inhibin rarely circulates freely in the blood. It combines with alpha2-macroglobulin protein. The administration of FSH increases the secretion of inhibin in normal men, but it is much more pronounced in males with secondary hypogonadism
Serum inhibin levels are strongly positively correlated with testicular volume and sperm counts. In infertile patients, inhibin decreases and FSH increases. In general, there is very good correlation with the degree of spermatogenesis damage, with the arrest at the earlier stages having the lowest inhibin levels
Inhibin and FSH together are a more sensitive and specific marker for spermatogenesis than either one alone
Suppression of spermatogenesis with testosterone and gestagens leads to a partial reduction of inhibin in serum, but it is never completely suppressed. In contrast, testicular irradiation leads to rapid and dramatic decrease of inhibin , which becomes undetectable when germ cells are completely absent
In summary: Inhibin is considered one of the best hormones in detecting the spermatogenesis status in males. It can predict testicular damage and correlates with testicular size. Its measurement may give an invaluable assessment of male infertility
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We, in the First Medical Laboratory, are dedicated to bring the best of laboratory medicine to clinical practice to Jordan
Dr. Hussam Abu-Farsakh
American Board of Anatomic & Clinical Pathology, and Cytopathology
“Circular” is a periodic circular that distributed to clinician informing them about new and important tests available at First Medical Laboratory. All information listed are supported by recent literature