Synthesis of Albumin and Acute-Phase Proteins in Perfused Liver after Burn Injury in Rats

Abstract

The acute-phase response that follows injury and sepsis is characterized by increased hepatic synthesis of specific secreted proteins while production of albumin is decreased. The effect of burn injury on specific synthesis rates of secreted hepatic proteins has not been reported. In this study, Sprague-Dawley rats received either a 30% flame burn (n = 12) or a sham burn (n = 12) and were allowed to recover for 11 days. Burned animals showed slower weight gains and a 25% to 30% higher resting energy expenditures compared with controls. On postburn day 11, synthesis of secreted hepatic proteins was measured by incorporation of leucine during a 2-hour isolated liver perfusion. Synthesis of total secreted proteins, the seromucoid fraction, and complement component C3 was significantly increased in burned animals, whereas synthesis of albumin was unaltered. In spite of unchanged albumin synthesis, plasma albumin concentrations were 50% lower in burned animals than in control animals throughout the postburn period. These findings suggest that decreased albumin synthesis is not the only mechanism responsible for persistent hypoalbuminemia that follows burn injury.