Analysis of urinary aldosterone metabolites in the guinea-pig

Analysis of urinary metabolites of [1, 2-3H]-aldosterone was performed in the male guinea-pig. Separation of urinary metabolites was carried out by countercurrent distribution followed by DEAE-Sephadex A-25 column chromatography. A major component was obtained which was both hydrolyzable with sulphatase from Helix pomatia and solvolyzable. Paper chromatography of freed steroids revealed the presence of at least two components and the major aglycone cochromatographed with 3 beta, 5 alpha-tetrahydroaldosterone. In order to get more information about the structure of urinary metabolites, a total of 68 mg of aldosterone was injected into three male guinea-pigs and separation of urinary metabolites was performed in a similar manner. A major component obtained showed the color reaction positive for sulphate (modified rhodizonic acid test) and negative for glucosiduronate (naphthoresorcinol test). Gas chromatographic-mass spectrometric analysis of aglycones released from this conjugate revealed the presence of 3 beta, 5 alpha-tetrahydroaldosterone and an another aglycone, tentatively identified as 21-deoxy-tetrahydroaldosterone. Taken together, it was concluded that 3 beta, 5 alpha-tetrahydroaldosterone-monosulphate and 21-deoxy-tetrahydroaldosterone-monosulphate comprised most of urinary conjugated metabolites of aldosterone in the male guinea-pig.