BETA-BLOCKADE LOWERS PERIPHERAL LIPOLYSIS IN BURN PATIENTS RECEIVING GROWTH-HORMONE - RATE OF HEPATIC VERY-LOW-DENSITY LIPOPROTEIN TRIGLYCERIDE SECRETION REMAINS UNCHANGED

Objective The purpose of this study was to determine the effect of pro pranolol on peripheral lipolysis in massively burned children during t reatment with recombinant human growth hormone (rhGH), and to ascertai n whether decreased free fatty acid availability for re-esterification would alter the hepatic rate of secretion of triglycerides (TGs) boun d to very low density lipoproteins (VLDLs). Background Fatty liver occ urs in severely burned patients, often resulting in a twofold increase in liver size. This could be the result of an imbalance between incre ased provision of free fatty acids from peripheral lipolysis, coupled with no increase in fat oxidation, and insufficient rate of secretion of TGs from the liver. Methods In a cross-over study, six burned child ren were treated with either rhGH or rhGH plus propranolol. On the six th day of treatment, isotopic tracer infusions were conducted to deter mine the rate of release of free fatty acid (Ra FFA) from peripheral t issue and the rate of secretion of VLDL-bound TGs by the liver. Result s Exogenous rhGH increased Ra FFA in children with large third-degree burns. Propranolol decreased Ra FFA, but the rate of secretion of fatt y acids in the form of VLDL-TG from the liver was maintained. Plasma F FA, as opposed to fatty acids newly synthesized in the liver, were the primary precursors for hepatic triglyceride synthesis. Conclusions Th e administration of propranolol to burned children receiving rhGH is s afe, has salutary cardiovascular effects, decreases the release of FFA from adipose tissue and increases the efficiency of the liver in secr eting fatty acids as VLDL TGs.