Effect of endotoxin on myocardial lipid metabolism
- VernacularTitle:内毒素对心肌脂质代谢的影响
- Author:
Xin WANG
;
Xiaodong WEI
;
Yanlin WANG
- Publication Type:Journal Article
- Keywords:
Endotoxins;
Myocardium;
Lipids;
Metabolism
- From:
Chinese Journal of Anesthesiology
1996;0(09):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To examine the effect of endotoxin on myocardial lipid metabolism and determine it′s possible mechanism Methods Sixty nine male Wistar rats (350 450g) were randomly divided into 2 groups: in vivo group and in vitro group In in vivo group endotoxin 0 1?g?kg -1 (small dose)or 1mg?kg -1 (large dose) was injected intrabdominally 3h after endotoxin administration the animals were anesthetized Heart was excised and passively perfused in a Laugendorff apparatus with oxygenated Krebs Heuseleit buffer at 37℃ Non esterified fatty acids (NEFA)and triacylglycerols(TAG) were used as energy supplying substance when the isolated heart had been stabilized for 15min NEFA or TAG was slowly added to the perfusate circuit 1 ml of perfusate was drawn every 10 min until the end of experiment (80 min ) for determination of the effects of endotoxin on NEFA or TAG oxidation and utilization by isolated heart At the end of experiment heart was harvested and frozen for measurement of myocardial lipids and lipoprotein lipase activity In in vitro group endotoxin was added to perfusate (1mg/ml) after the heart was excised and passively perfused In control group endotoxin was replaced by normal saline Results Large dose of endotoxin administered in vivo decreased NEFA oxidation rate by 30% in perfused isolated heart and caused increased accumulation of lipid in myocardial tissue By contrast endotoxin administered in vitro increased oxidation rate of TAG accompanied by an increase in myocardial lipoprotein lipase activity Administration of endotoxin in vivo and in vitro also caused accumulation of various exogenous lipids in myocardium in both NEFA and TAG perfused heart Conclusions This study shows that endotoxin has a significant effect on myocardial lipid metabolism The effect of endotoxin could be either direct or indirect according to the different lipids available