Demonstration of plasma human chorionic gonadotropin beta-subunit during pregnancy using LH-hCG receptors from immature porcine testis.
In an attempt to provide better assessment of human chorionic gonadotropin beta-subunit (hCG-beta) secretion in pregnant women, a method was developed for complete removal of hCG by porcine-purified receptors before measurement of the free hCG-beta subunit by radioimmunoassay. Blood samples of 111 pregnant women were collected and the following results were obtained: (1) Extensive removal (over 96%) of hCG allows quantitative determination of the free hCG-beta subunit by a specific radioimmunoassay. Our data demonstrate the presence of circulating hCG-beta subunit during pregnancy, a fact that was still under controversy until now. (2) In contrast with the hCG profile drug during pregnancy the free hCG-beta subunit exhibits a plasma concentration peak (400 +/- 132 ng/ml; mean +/- 1 SD) at the 12th-13th week, indicating that the changes in plasma levels of intact hCG and free hCG-beta subunit are unrelated.
D000818:Animals; D006063:Chorionic Gonadotropin / Q000097:blood* / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D011247:Pregnancy; D011863:Radioimmunoassay; D011956:Receptors, Cell Surface / Q000378:metabolism*; D011974:Receptors, LH; D011986:Receptors, Somatotropin; D013552:Swine; D013737:Testis / Q000378:metabolism
D006063:Chorionic Gonadotropin; D011956:Receptors, Cell Surface; D011974:Receptors, LH; D011986:Receptors, Somatotropin