Angel J F, Back D W
J Nutr. 1981 Oct;111(10):1805-15. doi: 10.1093/jn/111.10.1805.
Male, Sprague-Dawley rats were weaned prematurely (post-natal day 17) to a starch-based diet. Compared with normally-weaned rats, prematurely-weaned animals showed increases in the activities of hepatic glucose-6-phosphate dehydrogenase (G6PD) and malic enzyme (ME), and a fall in serum cholesterol level within 1 day. These enzymatic changes occurred sooner and were more pronounced when the diet of prematurely-weaned rats supplied 20% of the energy from sucrose, but the initial fall in serum cholesterol levels was smaller than in animals weaned prematurely to the control diet. Sucrose also led to an early rise in the activity of hepatic triokinase, but did not influence ketohexokinase or fructose-1-phosphate aldolase. Sucrose consumption resulted in an increase in lipogenesis in vivo in the liver and carcass and in serum cholesterol concentration on postnatal day 30, but animals weaned to the control diet were comparable with normally-weaned rats at the time. Early weaning led to elevation in the activities of hepatic G6PD and ME in 122-day-old rats, even though the control diet was fed from the age of 30 days. This response was not altered by the type of carbohydrate fed during the initial weaning period. Sucrose consumption during the weaning period did not exert long-term effects on the activities of hepatic fructolytic enzymes or in serum cholesterol levels.
雄性斯普拉格-道利大鼠在出生后第17天提前断奶，改为以淀粉为基础的饮食。与正常断奶的大鼠相比，提前断奶的动物在1天内肝脏葡萄糖-6-磷酸脱氢酶（G6PD）和苹果酸酶（ME）的活性增加，血清胆固醇水平下降。当提前断奶大鼠的饮食中20%的能量来自蔗糖时，这些酶的变化出现得更早且更明显，但血清胆固醇水平的初始下降幅度小于提前断奶至对照饮食的动物。蔗糖还导致肝脏磷酸丙糖激酶的活性早期升高，但不影响己糖激酶或果糖-1-磷酸醛缩酶。在出生后第30天，摄入蔗糖导致肝脏和胴体的体内脂肪生成增加以及血清胆固醇浓度升高，但此时断奶至对照饮食的动物与正常断奶的大鼠相当。即使从30日龄开始喂食对照饮食，提前断奶也会导致122日龄大鼠肝脏G6PD和ME的活性升高。这种反应不受断奶初期所喂碳水化合物类型的影响。断奶期间摄入蔗糖对肝脏果糖分解酶的活性或血清胆固醇水平没有长期影响。
