Analysis of urinary aldosterone metabolites in the rabbit by gas chromatography-mass spectrometry.

After a large amount of aldosterone was injected into a male rabbit, urine was collected for 48 h. Separation of urinary aldosterone metabolites into monoglucosiduronate fraction and monosulphate fraction was carried out by a combination of countercurrent distribution and DEAE-Sephadex A-25 column chromatography. Each fraction was hydrolyzed with enzyme and free steroids released were separated by Sephadex LH-20 column chromatography. The free steroid was then identified by gas chromatography-mass spectrometry. In monoglucosiduronate fraction, 3 alpha, 5 beta-tetrahydroaldosterone and 3 beta, 5 alpha-tetrahydroaldosterone were found. On the other hand, 3 alpha, 5 beta-tetrahydroaldosterone was the only aglycone detected in monosulphate fraction. These findings comfirmed results in the preceding paper, where the free steroid was characterized on the basis of the mobility of the steroid and its derivatives on paper chromatography.