Pugalendi K V, Ramakrishnan S
Department of Biochemistry, Annamalai University, Annamalainagar 608 002.
Indian J Exp Biol. 2000 Aug;38(8):762-5.
Small intestines synthesize cholesterol to a greater extent than liver. Between starch-fed and sucrose-fed rats, using (14C) glucose, it was found that the synthesis of cholesterol by the jejunum of small intestines was greater in the sucrose-fed group than starch-fed group. By a novel experimental technique and using (14C) glucose, it was found that the contribution towards buffer representing lymph was greater in the sucrose-fed group (13.3%) than the controls (11%). Hypercholesterolemia on sucrose feeding may be at least partly due to contribution by the small intestines. Regarding alcohol, using (14C) glucose it was found that total synthesis of cholesterol by the small intestines was decreased in alcohol-fed rats. There was no difference in the cholesterol retained by the intestinal tissue between the controls and alcohol-fed animals while, the secretion towards buffer (lymph) was 9% as against 11. This indicates that there is contribution of cholesterol to blood from small intestines in alcohol-intake also but due to overall decrease in the intestinal synthesis of cholesterol, contribution of intestines to hypercholesterolemia may not be substantial as in the case of sucrose feeding. This is because in sucrose-feeding there is increased cholesterol synthesis.
小肠合成胆固醇的程度比肝脏更高。在喂食淀粉和喂食蔗糖的大鼠之间,使用(14C)葡萄糖发现,喂食蔗糖组小肠空肠中胆固醇的合成比喂食淀粉组更多。通过一种新的实验技术并使用(14C)葡萄糖发现,喂食蔗糖组对代表淋巴的缓冲液的贡献(13.3%)大于对照组(11%)。喂食蔗糖导致的高胆固醇血症可能至少部分归因于小肠的作用。关于酒精,使用(14C)葡萄糖发现,喂食酒精的大鼠小肠中胆固醇的总合成减少。对照组和喂食酒精的动物之间肠道组织保留的胆固醇没有差异,而向缓冲液(淋巴)的分泌分别为9%和11%。这表明在摄入酒精时小肠也会向血液中贡献胆固醇,但由于小肠胆固醇合成总体减少,与喂食蔗糖的情况相比,小肠对高胆固醇血症的作用可能不显著。这是因为在喂食蔗糖时胆固醇合成增加。