The metabolism of some steroids has been investigated in liver microsomal preparations from male germ free and conventional rats. Hydroxylation of 4 [4-14C]androstene 3,17 dione in positions 6β and 16α is about 2 and 1.5 times more efficient in germ free than in conventional rats. The same is true for 6β and 2α hydroxylation of 4 [4 14C]pregnene 3,20 dione (about 1.6 and 1.2 times larger, respectively, in germ free animals), for 18 hydroxylation of 5α[4 14C] androstane 3α, 17β diol (about 1.6 times larger in germ free rats), and for 6β hydroxylation of lithocholic acid (about 2 times larger in germ free rats). All these differences are statistically significant (significance level, p < 0.05). Similar differences (although not statistically significant) are also found for 16α hydroxylation of 4 pregnene 3,20 dione and for 2β and 2α hydroxylation of 5α androstane 3α, 17β diol. The amount of cytochrome P 450 in germ free animals is 2.53 ± 0.45 nmoles per mg of protein as compared to 1.72 ± 0.04 nmoles per mg of protein in conventional animals (p < 0.005). 5α Reduction of 4 androstene 3,17 dione, 4 pregnene 3,20 dione and of 7α [6β 3H]hydroxy 4 cholesten 3 one tends to be lower in germ free than in conventional rats. In contrast to these results, 12α hydroxylation of 7α hydroxy 4 cholesten 3 one and 7α hydroxylation of [4 14C] cholesterol are larger in conventional than in germ free rats. These findings are in accordance with the slower cholesterol and bile acid turnover in germ free compared to conventional rats.
|Original language||English (US)|
|Number of pages||8|
|Journal||Journal of Biological Chemistry|
|State||Published - 1973|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology