Subbiah M T, Yunker R L, Menkhaus A, Poe B
Am J Physiol. 1985 Sep;249(3 Pt 1):E251-6. doi: 10.1152/ajpendo.1985.249.3.E251.
Premature weaning in animals causes higher serum cholesterol levels and a relative inability to handle cholesterol challenge in adult life. The mechanisms responsible for these delayed effects of premature weaning are not clear. The aims of this investigation were to 1) determine the effect of premature weaning on the activity of hepatic cholesterol 7 alpha-hydroxylase and plasma cholesterol changes and 2) determine whether addition of cholesterol to the diet will restore premature weaning-induced changes. Premature weaning did not prevent the phenomenon of neonatal hypercholesterolemia noted in day 5 of normally weaned guinea pigs. At day 10, prematurely weaned animals had lower serum cholesterol when compared with normally weaned animals. Premature weaning caused (without or with cholesterol in diet) a significant decrease in the hepatic activity of cholesterol 7 alpha-hydroxylase, and this difference persisted (after 1 mo) when fed the stock diet. These studies demonstrate 1) premature weaning on day 2 does not prevent neonatal hypercholesterolemia on day 5, 2) premature weaning causes a decrease in hepatic cholesterol 7 alpha-hydroxylase activity that persists into adult life, and 3) dietary cholesterol intake in early life is unable to negate premature weaning-induced changes.
动物过早断奶会导致血清胆固醇水平升高，并且在成年后相对无法应对胆固醇挑战。导致过早断奶出现这些延迟效应的机制尚不清楚。本研究的目的是：1）确定过早断奶对肝脏胆固醇7α-羟化酶活性和血浆胆固醇变化的影响；2）确定在饮食中添加胆固醇是否能恢复过早断奶引起的变化。过早断奶并未阻止正常断奶豚鼠在第5天时出现的新生儿高胆固醇血症现象。在第10天时，与正常断奶的动物相比，过早断奶的动物血清胆固醇较低。过早断奶（无论饮食中是否含有胆固醇）都会导致肝脏胆固醇7α-羟化酶活性显著降低，并且在喂食常规饲料时，这种差异会持续存在（1个月后）。这些研究表明：1）第2天过早断奶并不能预防第5天的新生儿高胆固醇血症；2）过早断奶会导致肝脏胆固醇7α-羟化酶活性降低，这种降低会持续到成年期；3）生命早期的饮食胆固醇摄入无法消除过早断奶引起的变化。
