Female Pattern of Metabolism of [4-¹⁴C]Corticosterone in Male Pseudohermaphroditic Rats

The metabolites of [4-¹⁴C]corticosterone appearing in bile fistulae of male pseudohermaphrodites and littermate male and female Stanley-Gumbreck rats were determined by gas-liquid chromatography, radio-gas chromatography and gas chromatog-raphy-mass spectrometry. Male pseudohermaphroditic rats excrete corticosterone metabolites identical to those in bile from female rats: 3 a,11 β,21-trihydroxy-5 a -pregnan-20-one and 3 a, 11β, 15 a,21-tetrahydroxy-5 a -pregnan-20-one in the monosulfate fraction and, and 3 a, 11β,21-trihydroxy-5 a -pregnan-20-one, 3 a, 11β, 15 a,21-tetrahydroxy-5 a -pregnan-20-one, and 3β,11β,21-trihydroxy-5 a -pregnan-20-one in the disulfate fraction. Male rats excrete 5 a -pregnane-3β,11β,20β,21-tetrol in the monosulfate fraction and 3β,11β,21-trihydroxy-5 a -pregnan-20-one and 5 a -pregnane-3β,11β,20β,21-tetrol in the disulfate fraction. The female type of corticosterone metabolism in the male pseudohermaphroditic rat is probably due to the lack in these animals of a postnatal testosterone imprinting effect on the liver combined with hepatic insensitivity to testosterone in adult life. Large doses of testosterone propionate completely suppress the excretion of 3 a,11β,15 a,21-tetrahydroxy-5 a -pregnan-20-one in bile from a pseudoher-maphroditic rat indicating a relative rather than an absolute testosterone insensitivity of the liver of these rats. The authors are grateful to Drs. A. J. Stanley, J. E. Allison, and L. G. Gumbreck for supplying the male pseudohermaphroditic and littermate rats.