To identify the metabolic basis of postweaning differences in bile acid synthesis (BAS) due to BRand F-feeding in baboons, we measured total BAS kinetically and hepatic microsomal activities of cholesterol 7α-hydroxylase (7α-OHase) and 27hydroxycholesterol 7α-hydroxylase (27OH-7α-OHase) by GLC-mass spectrometry. Of 6 baboons, 3 were BR-fed and 3 F-fed until 15 weeks. Measurements were made at 4 years of age on a low cholesterol chow diet and on a high cholesterol, saturated fat diet (HC-SF). BR-fed baboons had 74% higher total bile acid pool size (P < 0.03) and a 41% lower BAS (P= 0.11) compared with those fed F. Lower BAS among BR-fed animals was consistent with a 52% lower 7aOHase activity (P = NS). 27OH-7α-OHase activity was similar among BR- and F-fed animals. On the HC-SF diet, total BAS and 7o-OHase activities were 54% (P < 0.04) and 62% (P=NS) respectively of those measured on the chow diet. 27OH-7α-OHase activity was similar on the chow and HC-SF diets. These results suggest that programmed effects of BR- and F-feeding on BAS are mediated by effects on 7αOHase activity and feeding a HC-SF diet decreases BAS.
|Original language||English (US)|
|State||Published - Dec 1 1996|
ASJC Scopus subject areas
- Molecular Biology