Injury-induced inhibition of fat absorption.

Burn injury inhibits lipoprotein lipase, which leads to an impeded clearance of triglycerides from the plasma and an increase in serum triglycerides. Intestinal brush border lipase, which hydrolyzes triglyceride to free fatty acids and is essential for absorption of triglycerides from the gastrointestinal tract, could also be inhibited by burn injury. In thermally injured rats, the absorption and oxidation of enterally administered 14C-palmitate triglyceride, brush border lipase activity, and small-intestinal and colonic content of fat were determined. Absorption of 14C-palmitate triglyceride and production of 14CO2 were reduced 50% 18 hours after injury (p < 0.01). In addition, brush border lipase activity was reduced 50% (p < 0.01). Because brush border lipase function is essential to the proper absorption of enterally administered fat, inhibition of intestinal lipase could be an important factor in enteral diet effectiveness.