Edwards P A, Lemongello D, Fogelman A M
J Lipid Res. 1979 Jan;20(1):2-7.
Incubation of rat hepatocytes for 3 hours in a sterol-free medium containing 1.5% albumin resulted in efflux of cellular sterol into the medium and an increased activity of 3-hydroxy-3-methylglutaryl CoA reductase. The secretion of cholesterol was inhibited when cells were incubated with glucagon, norepinephrine, or dibutyryl cyclic AMP. Glucagon and dibutyryl cyclic AMP also inhibited the induction of HMG-CoA reductase. Norepinephrine treatment resulted in a decrease in the synthesis and secretion of proteins but caused an increase in reductase activity. Insulin treatment had no effect either on reductase activity or on sterol efflux from rat hepatocytes.
将大鼠肝细胞在含有1.5%白蛋白的无甾醇培养基中孵育3小时，导致细胞甾醇外流到培养基中，并使3-羟基-3-甲基戊二酰辅酶A还原酶的活性增加。当细胞与胰高血糖素、去甲肾上腺素或二丁酰环磷酸腺苷一起孵育时，胆固醇的分泌受到抑制。胰高血糖素和二丁酰环磷酸腺苷也抑制HMG-CoA还原酶的诱导。去甲肾上腺素处理导致蛋白质合成和分泌减少，但使还原酶活性增加。胰岛素处理对大鼠肝细胞的还原酶活性或甾醇外流均无影响。
