Sakono M, Mori H, Nagao K, Sato M, Ikeda I, Yamamoto K, Imaizumi K
Department of Food Science and Technology, Faculty of Agriculture, Kyushu University, Fukuoka, Japan.
Comp Biochem Physiol B Biochem Mol Biol. 1996 Apr;113(4):803-8. doi: 10.1016/0305-0491(95)02105-1.
Early responses of cholesterol metabolism to dietary cholesterol were compared between exogenous hypercholesterolemic (ExHC) and Sprague-Dawley rats. Both strains had a similar radioactivity of [14C]cholesterol in the serum half a day after the oral administration, but thereafter the radioactivity disappeared slowly in ExHC rats. ExHC rats promptly altered in response to the dietary cholesterol, activities of cholesterol 7 alpha-hydroxylase and cholesterol synthesis in the liver and fecal excretion of bile acids derived from [14C]cholesterol administered orally. Lymphatic transport for 24 hr [14C]cholesterol was similar between the strains. Triton administration resulted in a marked accumulation of cholesterol in serum d > 1.006 g/mL lipoproteins in ExHC rats; in addition, the formation of cholesteryl esters from [14C]oleic acid intravenously infused was greater in ExHC rats. These results indicate that ExHC rats increase serum cholesterol in response to exogenous cholesterol by decreasing the liver uptake and enhancing the secretion in the liver.
比较了外源性高胆固醇血症（ExHC）大鼠和斯普拉格-道利大鼠对膳食胆固醇的胆固醇代谢早期反应。两种品系在口服给药后半天血清中[14C]胆固醇的放射性相似，但此后ExHC大鼠中的放射性消失缓慢。ExHC大鼠对膳食胆固醇迅速产生反应，肝脏中胆固醇7α-羟化酶活性和胆固醇合成以及口服[14C]胆固醇衍生的胆汁酸的粪便排泄均发生改变。两种品系之间24小时[14C]胆固醇的淋巴转运相似。给予曲拉通导致ExHC大鼠血清d>1.006 g/mL脂蛋白中胆固醇显著积累；此外，ExHC大鼠中静脉注射[14C]油酸形成胆固醇酯的量更大。这些结果表明，ExHC大鼠通过减少肝脏摄取并增强肝脏分泌来对外源性胆固醇作出反应，从而增加血清胆固醇。
