The measurement of 11 beta-hydroxy-4-pregnene-3,20-dione (21-deoxycorticosterone) by radioimmunoassay in human plasma.
A specific radioimmunoassay (RIA) method is described for the determination of 21-deoxycorticosterone (21 DB) in human plasma. 21-Deoxycorticosterone-3-(O-carboxymethyl) oxime-bovine serum albumin conjugate was used to generate antisera in rabbits. Steroids which reacted significantly with the antisera were found to be progesterone, pregnenolone, corticosterone and 11-oxo progesterone. However, after extraction of plasma and column chromatography on Celite, all these steroids were separated from 21-deoxycorticosterone and consequently did not interfere with the radioimmunoassay. The intra- and interassays coefficients of variation were 8% and 11% respectively. Mean plasma 21-deoxycorticosterone level for healthy subjects was very low: 17.8 +/- 14.8 pmol/l (mean +/- SD) with no statistical difference between males and females. During the ACTH stimulation test, the 21-deoxycorticosterone levels of healthy subjects increased to 84.7 +/- 26.3 pmol/l (mean +/- SD) for males and 79.3 +/- 31.6 pmol/l (mean +/- SD) for females. Consequently high levels of plasma 21-deoxycorticosterone were found in treated patients suffering from congenital adrenal hyperplasia (CAH) with 21-hydroxylase deficiency, particularly in CAH salt-losers with high plasma renin activity (PRA), where the plasma level reached 40,545 pmol/l. Thus, 21-deoxycorticosterone may be a new marker for adrenal 21-hydroxylase deficiency.
D019326:17-alpha-Hydroxyprogesterone; D000293:Adolescent; D000312:Adrenal Hyperplasia, Congenital / Q000097:blood*; D000328:Adult; D000918:Antibody Specificity; D002648:Child; D002675:Child, Preschool; D003350:Cortodoxone / Q000097:blood; D003429:Cross Reactions; D003900:Desoxycorticosterone / Q000097:blood*; D005260:Female; D006801:Humans; D006908:Hydroxyprogesterones / Q000097:blood*; D008297:Male; D011863:Radioimmunoassay; D012083:Renin / Q000097:blood
D006908:Hydroxyprogesterones; C030228:11-hydroxyprogesterone; D003900:Desoxycorticosterone; C003556:21-deoxycortisol; D019326:17-alpha-Hydroxyprogesterone; D012083:Renin; D003350:Cortodoxone