Increased 17 beta-hydroxysteroid dehydrogenase activity in a masculinizing adrenal adenoma in a patient with isolated testosterone overproduction.
The patient studied had noted the onset of virilization shortly after menopause. Urinary 17-ketosteroid levels were normal, as were fractionated 17-ketosteroid levels by gas liquid chromatography, but for 3 yr, serum testosterone levels had been greater than 490 ng/dl. The ovaries were found to be normal by laparoscopy. Abdominal exploration revealed a 1-cm adenoma in the right adrenal. A part of the adenoma excised from our patient was homogenized and incubated with 5 microCi [14C]androstenedione. Five percent of the 14C was converted by the tumor homogenate to a metabolite with the same mobility as testosterone on LH-20 chromatography. After thin layer chromatography, the radiolabeled material together with 3H-labeled authentic testosterone were crystallized to a constant specific activity. The net rate of testosterone synthesis by the tumor was 26 pmol/mg wet tissue wt.h vs. 0.56 pmol/mg.h by a control adrenal homogenate. Thus, the tumor demonstrated a 50-fold increase in 17 beta-hydroxysteroid dehydrogenase activity compared to normal adrenal tissue. This is the first report to identify altered activity of a specific enzyme system in this syndrome of isolated adrenal testosterone overproduction.
D015067:17-Hydroxysteroid Dehydrogenases / Q000378:metabolism*; D000236:Adenoma / Q000201:enzymology*; D000310:Adrenal Gland Neoplasms / Q000201:enzymology*; D000368:Aged; D000735:Androstenedione / Q000378:metabolism; D005260:Female; D006801:Humans; D008593:Menopause; D013739:Testosterone / Q000096:biosynthesis*; D014770:Virilism / Q000201:enzymology*
D013739:Testosterone; D000735:Androstenedione; D015067:17-Hydroxysteroid Dehydrogenases