Simultaneous determination of 15 steroids in rat blood via gas chromatography–mass spectrometry to evaluate the impact of emasculation on adrenal

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, 17α-hydroxyprogesterone (17αP), 17α-hydroxypregnenolone (17αH), dehydroepiandrosterone (DHEA), estrone, 17β-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 (17αH, 17αP) 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.