Cagen L M, Fungwe T V, Wilcox H G, Heimberg M
Department of Pharmacology, University of Tennessee, Memphis 38163.
Biochem Biophys Res Commun. 1992 Feb 28;183(1):21-6. doi: 10.1016/0006-291x(92)91602-m.
Livers isolated from adult male rats were perfused in vitro with oleic acid (0.6 mM) as a complex with bovine serum albumin. Albumin alone was infused in control experiments. Oleic acid exerted a biphasic effect on incorporation of 3H2O into cholesterol, which was inhibitory during the first hour of perfusion, but exhibited a net stimulatory effect over a four hour period. No differences were observed in total activity or apparent phosphorylation state of HMG-CoA reductase after one hour of perfusion, with or without addition of oleic acid, implying that some other step limits the rate of cholesterol synthesis during this interval. After four hours of perfusion, HMG-CoA reductase activity was higher in livers perfused with oleic acid than in those perfused in its absence, in agreement with the observed differences in rates of cholesterol synthesis.
从成年雄性大鼠分离出的肝脏在体外以油酸（0.6 mM）与牛血清白蛋白的复合物进行灌注。在对照实验中单独输注白蛋白。油酸对3H2O掺入胆固醇具有双相作用，在灌注的第一个小时具有抑制作用，但在四个小时的时间段内表现出净刺激作用。灌注一小时后，无论是否添加油酸，HMG-CoA还原酶的总活性或表观磷酸化状态均未观察到差异，这意味着在此期间其他一些步骤限制了胆固醇合成的速率。灌注四小时后，用油酸灌注的肝脏中HMG-CoA还原酶活性高于未用油酸灌注的肝脏，这与观察到的胆固醇合成速率差异一致。
