Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0338671 (Steroids)
 9,479 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

17alpha-hydroxypregnenolone (17OHPreg) has heretofore been considered to be the major cause of the false elevated 17alpha-hydroxyprogesterone (17OHP) value in the immunoassay-based newborn screening for congenital adrenal hyperplasia (CAH). To verify this point, we developed a liquid chromatography-tandem mass spectrometric (LC-MS/MS) method that enables the simultaneous quantification of 17OHPreg and 17OHP in the dried blood filter papers and measured their blood levels in infants, especially in infants with low birth weights. Steroids were extracted from the filter papers with methanol, purified using a Strata-X cartridge, derivatized with 2-hydrazinopyridine and subjected to LC-MS/MS. Validation tests proved that this method was specific and reproducible; endogenous steroids did not interfere with the quantifications, and the intra- and inter-assay coefficients of variation were below 5.2%. The limits of quantitation were 1.0 and 0.5 ng/mL for 17OHPreg and 17OHP, respectively, when 3 disks (3 mm in diameter) of the filter papers (corresponding to 8 microL of whole blood) were used. The blood 17OHPreg level was elevated in the very low birth weight (1000-1500 g) infants and extremely low birth weight (<1000 g) infants, compared to those in the normal birth weight (>2500 g) infants (P<0.05). However, the 17OHPreg concentration was not high enough to cause the false positive results in the enzyme immunoassay-based screening, and it was considered that the false positive results come from other endogenous components rather than 17OHPreg.
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PMID:Simultaneous determination of 17alpha-hydroxypregnenolone and 17alpha-hydroxyprogesterone in dried blood spots from low birth weight infants using LC-MS/MS. 1857 54

Adrenal was believed to affect the prostate tumor tissue growth by its secretion of adrenal androgens. However, the mechanisms regulating these effects were not fully understood. In this work, a sensitive and specific method for the determination of 15 steroids in blood via gas chromatography-mass spectrometry in selective ion storage detection mode was established to evaluate the impact of emasculation on adrenal steroids metabolism. Steroids were isolated by solid-phase extraction using Oasis HLB cartridge, and then derivated with heptafluorobutyric anhydride before analysis. The limits of detection were between 0.15 and 1.0 ng/mL and limits of quantification were between 0.62 and 2.6 ng/mL. The recoveries of steroids were above 83%, and both the intra-day and inter-day precisions (RSD%) were lower than 8%. Pregnenolone, progesterone, 17alpha-hydroxyprogesterone (17alphaP), 17alpha-hydroxypregnenolone (17alphaH), dehydroepiandrosterone (DHEA), estrone, 17beta-estradiol, dihydrotestosterone (DHT), testosterone (T), 4-androstenedione (4-A), 1,4-androstadiene-3,17-dione, 11-deoxycortisol, 11-deoxycorticosterone, cortisol and aldosterone were quantified in 156 major male SD rats at 0, 1, 2, 4, 7 days, 2, 4, 6, 8, 10, 12, 14, and 16 weeks following emasculation. T and DHT decreased by 86.2% and 73.4%, respectively in the first 7 days following emasculation, but adrenal androgens (DHEA, 4-A) stabled at the normal level accordingly. Adrenal androgens and their precursors (17alphaH, 17alphaP) increased from the 2nd week along with the increase of androgens and the decrease of mineralocorticoids. These facts revealed that adrenal possibly enhanced its function of producing adrenal androgens from the 2nd week responding to the low androgens level induced by emasculation.
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PMID:Simultaneous determination of 15 steroids in rat blood via gas chromatography-mass spectrometry to evaluate the impact of emasculation on adrenal. 1983 59


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