Lipoprotein lipase activity in rat heart and adipose tissue during endotoxic shock

The present studies were designed to delineate changes in heart and adipose tissue lipoprotein lipase (LPL) activity following the administration of E. coli endotoxin. Plasma triglyceride levels were elevated in animals given endotoxin compared to saline-injected controls. Heart LPL activity decreased from 126.4 mumol fatty acid released per gram wet wt per hour in control rats to less than 22.5 mumol . g-1 . h-1 by 7 h following the injection of endotoxin. Although endotoxin was administered in doses producing 0-100% mortalities in a 24-h period, myocardial LPL activity was depressed to the same extent (75-80%) regardless of dose. The response of adipose tissue was less pronounced. Epididymal fat pad LPL activity fell significantly over the 24-h observation period in control and endotoxin-treated rats with the latter group somewhat more depressed 7 h after treatment. The findings are consistent with the suggestion that hypertriglyceridemia often observed during endotoxic shock may be related to depressed LPL activity; the degree of depression is probably tissue dependent.