Bioavailability of Albumin-Bound Testosterone

The study from 1985 focused on the bioavailability of albumin-bound testosterone (T) in the context of spironolactone treatment in hirsute women and its clinical implications. It involved nine premenopausal women and two normal men. The researchers found that spironolactone increased the non-TeBG-bound fraction of plasma T significantly, suggesting that albumin-bound T is biologically available and should be considered in the pool of bioavailable T. The study also demonstrated that spironolactone and its metabolites displaced T from TeBG, increasing the fraction of brain bioavailable T. This displacement was confirmed using both the carotid artery injection technique and the ammonium sulfate precipitation method. The study concluded that the bioactive moiety of T includes a significant fraction of albumin-bound T, which is biologically available and may have clinical relevance in the treatment of hyperandrogenic states.