[Effect of postnatal administration of a microsomal enzyme inducer on development of their activity during early...

The effect of early postnatal introduction of the inductor of microsomal enzymes, 3-acetate-16alpha-isothiocyanopregnenolone (ATCP), on the activity of cholesterol-7alpha-hydroxylase (cholesterol-reduced NADP+: oxygen oxydoreductase; 7alpha-hydroxylating) was studied. The experiments were carried out with newborn cholesteremic SWR/j mice which were given ATCP per os from the 2nd till the 9th day of postnatal development. The introduction of ATCP was shown to induce cholesterol-7alpha-hydroxylase in the liver of experimental mice during the first month of life. 6 months after birth the content of atherogenic lipoproteins in the blood serum of experimental animals was reduced, as compared with the control ones, although the content of cholesterol in the blood serum and the activity of cholesterol-7alpha-hydroxylase in the liver were similar. Changes in the fractions of lipoproteins appear to be due to the early stimulation of cholesterol-7alpha-hydroxylase by the inductor.