Effect of high-level spinal cord injury on myocardial energy metabolism in rats / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the effect of high-level spinal cord injury (SCI) on the myocardial energy metabolism in rats.Methods Sixty healthy male Sprague-Dawley rats,weighing 250-300 g,were randomly divided into 2 groups (n=30 each) using a random number tablesham operation (group S) and SCI group.SCI was induced in anesthetized rats by dropping a 10 g weight onto C7 spinal cord from 5 cm height falling freely inside a vertical hollow glass tube.At 6,12,24,48 and 72 h after SCI,6 rats in each group were chosen and arterial blood samples were taken for measurement of serum creatine kinase (CK) and creatine kinase isoenzyme-MB (CK-MB) activities.The rats were then sacrificed and myocardial specimens were obtained for examination of myocardial ultrastructure and for determination of ATP weight ratio,levels of Na+-K+-ATPase,Ca2+-Mg2+-ATPase,non-esterified fatty acids (NEFA) and lactic acid (LD),and expression of peroxisome proliferator-activated receptor alpha (PPARα) mRNA and protein (using fluorescent quantitative PCR and Western blot).Results Compared with group S,the serum CK and CK-MB activities were significantly increased,the ATP weight ratio,activities of Na+-K+-ATPase and Ca2+-Mg2+-ATPase and levels of NEFA and LD were decreased,and the expression of PPAR-α mRNA and protein was down-regulated in SCI group.No pathological changes of myocardium were found in group S,and the pathological changes of myocardium were obvious in SCI group.Conclusion High-level SCI can lead to decrease in the myocardial energy metabolism in rats,and down-regulated expression of PPARα is involved in the mechanism.