年龄和日粮脂肪水平对新生仔猪脂肪酸氧化的影响。

Effect of age and dietary fat level on fatty acid oxidation in the neonatal pig.

作者信息

Wolfe R G, Maxwell C V, Nelson E C

出版信息

J Nutr. 1978 Oct;108(10):1621-34. doi: 10.1093/jn/108.10.1621.

DOI:10.1093/jn/108.10.1621

Abstract

A total of 35 pigs were obtained by cesarean section, placed in individual sterile isolators, and randomly allotted to treatment groups. Thirty pigs received purified, isoenergetic liquid diets containing 2 or 32% butterfat (dry matter basis) and were killed at 1, 7, or 21 days of age. Five pigs were killed at 2 hours post delivery and received no diet. Twenty-one-day old pigs showed a tendency for higher weight gain and feed consumption when consuming the 32% fat diet although the differences were not significant. The rate of oxidation of [U-14C]palmitate to CO2 and acid soluble products was measured in homogenates of liver, kidney, heart, and leg muscle (biceps femoris) from pigs 0, 1, 7, and 21 days of age. The relative rates of oxidation of [U-14C]myristate, [U-14C]palmitate, and [U-14C]stearate were measured in homogenates of liver from 7-day old pigs. Palmitate oxidation was stimulated by carnitine in all four tissues and the rate of carnitine-stimulated palmitate oxidation to acid soluble products in heart and to CO2 in liver was higher in tissues from pigs consuming the 32% fat diet. The rate of palmitate oxidation increased with age in liver, kidney and leg muscle tissues and was maximum at 21 days in kidney and leg muscle and at 7 days in liver. The rate of palmitate oxidation in heart tended to decrease with animal age. In homogenates of liver from 7-day old pigs, palmitate was oxidized at a faster rate than stearate or myristate. The activities of carnitine palmitoyltransferase (CPT) (EC 2.3.1a) and succinate dehydrogenase (EC 1.3.99.1) in mitochondria isolated from liver, kidney, heart, and leg muscle did not vary considerably with age although CPT activity tended to be higher in those tissues from pigs consuming the high fat diet. Changes in the rate of palmitate oxidation with age tended to parallel changes in the level of mitochondrial protein per g of wet tissue and suggested an increased ability to utilize fat as an energy substrate during early development of the neonatal pig.

摘要

通过剖腹产获得35头仔猪，将其置于单独的无菌隔离器中，并随机分配到各处理组。30头仔猪接受了含有2%或32%乳脂肪（以干物质计）的纯化等能量液体日粮，并在1日龄、7日龄或21日龄时宰杀。5头仔猪在分娩后2小时宰杀，未接受日粮。尽管差异不显著，但21日龄的仔猪在食用32%脂肪日粮时体重增加和采食量有增加的趋势。测定了0日龄、1日龄、7日龄和21日龄仔猪肝脏、肾脏、心脏和腿部肌肉（股二头肌）匀浆中[U-14C]棕榈酸氧化为二氧化碳和酸溶性产物的速率。测定了7日龄仔猪肝脏匀浆中[U-14C]肉豆蔻酸、[U-14C]棕榈酸和[U-14C]硬脂酸的相对氧化速率。在所有四种组织中，肉碱均刺激棕榈酸氧化，且在食用32%脂肪日粮的仔猪组织中，肉碱刺激的棕榈酸氧化为酸溶性产物在心脏中的速率以及氧化为二氧化碳在肝脏中的速率更高。在肝脏、肾脏和腿部肌肉组织中，棕榈酸氧化速率随年龄增加，在肾脏和腿部肌肉中21日龄时达到最高，在肝脏中7日龄时达到最高。心脏中棕榈酸氧化速率随动物年龄增长有下降趋势。在7日龄仔猪的肝脏匀浆中，棕榈酸的氧化速率比硬脂酸或肉豆蔻酸快。从肝脏、肾脏、心脏和腿部肌肉分离的线粒体中肉碱棕榈酰转移酶（CPT）（EC 2.3.1a）和琥珀酸脱氢酶（EC 1.3.99.1）的活性随年龄变化不大，尽管在食用高脂肪日粮的仔猪的这些组织中CPT活性往往较高。棕榈酸氧化速率随年龄的变化趋势与每克湿组织中线粒体蛋白水平的变化趋势平行，这表明新生仔猪在早期发育过程中利用脂肪作为能量底物的能力增强。