Contribution of altered lipolysis and reesterification in perturbations of free fatty acid kinetics during burn shock.

We have previously shown that free fatty acid (FFA) mobilization is severely decreased during burn shock in the guinea pig. Glycerol mobilization was also decreased, indicating that decreased lipolysis was a major contributing factor to the impairment of FFA mobilization. In order to assess the contribution, if any, of increased FFA reesterification to the perturbations of FFA kinetics, we used the constant infusion technique, simultaneously infusing 14C-palmitate and 3H-glycerol. By this method we measured the rate of triglyceride hydrolysis (glycerol turnover) and the mobilization of FFA from adipose tissue (palmitate turnover). It was found that FFA turnover was decreased by 65% (39.4 +/- 4.1 to 16.7 +/- 1.4 mumole/kg . min, P less than 0.001), and glycerol turnover was decreased by 48% (23.6 +/- 2.5 to 12.3 +/- 1.1 mumole/kg . min, P less than 0.001) at 2 hr postburn. The FFA:glycerol ratio decreased from 1.87 +/- 0.20 to 1.43 +/- 0.15 (P less than 0.02), suggesting that increased FFA reesterification contributed to the decrease of FFA mobilization from adipose tissue during burn shock.