Sex hormone binding globulin: the carrier protein for d-norgestrel.
The binding of different synthetic steroids, used in hormonal contraception, to Sex Hormone Binding Globulin (SHBG) was studied by measuring their ability to displace tritiated testosterone from SHBG in a competitive protein binding system. Only 19-nortestosterone derivates had any significant ability to displace testosterone from SHBG, d-norgestrel (d-Ng) being the strongest displacer. Increasing the SHBG levels in women with previous constant plasma d-Ng levels increased these levels two- to sixfold. It is concluded that SHBG is the main carrier protein for d-Ng. The strong testosterone displacing activity of d-Ng might also explain androgenic side effects observed with d-Ng containig oral contraceptives.
D000152:Acne Vulgaris / Q000139:chemically induced; D001667:Binding, Competitive; D002352:Carrier Proteins / Q000378:metabolism*; D003276:Contraceptives, Oral / Q000009:adverse effects; D006628:Hirsutism / Q000139:chemically induced; D006801:Humans; D008297:Male; D009277:Nandrolone / Q000378:metabolism; D009644:Norgestrel / Q000378:metabolism*; D013739:Testosterone / Q000378:metabolism
D002352:Carrier Proteins; D003276:Contraceptives, Oral; D009644:Norgestrel; D013739:Testosterone; D009277:Nandrolone