Alejandre M J, Ramirez H, Segovia J L, Garcia-Peregrin E
Ann Nutr Metab. 1985;29(2):111-8. doi: 10.1159/000176968.
Supplementation of the diet with 2% cholesterol suppressed the increase observed in the hepatic and intestinal 3-hydroxy-3-methylglutaryl-CoA reductase activity from normally fed chicks during the first days after hatching. Cholestyramine feeding clearly increased both hepatic and intestinal reductase activities. In contrast, brain reductase did not show significant changes by cholesterol or cholestyramine feeding. Dietary cholesterol produced a clear increase in the cholesterol/lipidic phosphorus molar ratio of hepatic and intestinal microsomal membranes. However, this molar ratio did not change by cholestyramine feeding during postnatal development. Both dietary cholesterol and cholestyramine had practically no effect on the cholesterol/lipidic phosphorus molar ratio of brain microsomes. The relationship between the inhibition of reductase activity by dietary cholesterol and the increase of cholesterol/lipidic phosphorus molar ratio is in agreement with a mechanism of regulation of both hepatic and intestinal reductase by alterations of membrane fluidity, mechanism that would be already operative during the neonatal period.
在日粮中添加2%的胆固醇可抑制刚孵化出的雏鸡在出生后最初几天内，正常饲喂雏鸡肝脏和肠道中3-羟基-3-甲基戊二酰辅酶A还原酶活性的增加。喂食消胆胺明显增加了肝脏和肠道中的还原酶活性。相比之下，喂食胆固醇或消胆胺后，脑还原酶未显示出显著变化。日粮中的胆固醇使肝脏和肠道微粒体膜的胆固醇/脂质磷摩尔比明显增加。然而，在出生后的发育过程中，喂食消胆胺并未改变该摩尔比。日粮中的胆固醇和消胆胺对脑微粒体的胆固醇/脂质磷摩尔比几乎没有影响。日粮中的胆固醇对还原酶活性的抑制作用与胆固醇/脂质磷摩尔比的增加之间的关系，与通过膜流动性改变来调节肝脏和肠道还原酶的机制相一致，该机制在新生儿期可能已经起作用。
