No change in plasma free testosterone ratio and plasma sex hormone-binding globulin concentration during hCG stimulation.
Plasma sex hormone-binding globulin (SHBG) levels and free testosterone ratios were determined independently after administration of hCG for 4 consecutive days to eight normal men. Correcting for nonspecific dihydrotestosterone binding, no changes in plasma SHBG were found. The free testosterone ratio, measured by equilibrium dialysis, did not change despite doubling of total plasma testosterone. The increase in plasma testosterone after hCG stimulation was due to increased production only, with equivalent changes in free testosterone concentration, and was not a result of changes in SHBG concentration.
D006063:Chorionic Gonadotropin / Q000494:pharmacology*; D006801:Humans; D008297:Male; D011863:Radioimmunoassay; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism*; D013739:Testosterone / Q000097:blood*
D006063:Chorionic Gonadotropin; D012738:Sex Hormone-Binding Globulin; D013739:Testosterone