STUDIES ON THE ETIOLOGY OF ACUTE ACALCULOUS CHOLECYSTITIS - THE EFFECT OF LIPOPOLYSACCHARIDE ON HUMAN GALLBLADDER MUCOSAL CELLS

Previous studies in animals have shown that lipopolysaccharide produces experimental cholecystitis possibly through a platelet-activating factor-prostanoid mediated process. In this study it was intended to evaluate the effect of LPS on primary cultures of human gallbladder mucosal cells. Gallbladder mucosal cells were isolated from gallbladders removed during routine cholecystectomies or other operations. The cells were cultured for 24 h before treatment. Unstimulated cells produced low levels of prostanoids and significant basal levels of PAF. LPS produced stimulation of eicosanoid and PAF secretion. The increased prostanoid formation was not enhanced when LPS and PAF were administered together Prostanoid synthesis was inhibited by the administration of a cyclooxygenase inhibitor while administration of a PAF receptor antagonist significantly increased prostanoid formation, suggesting that increased PAF levels function as a negative control mechanism to decrease prostanoid synthesis. The results suggest that endotoxemia may produce a cascade of inflammatory processes in human gallbladder mucosal cells resulting in the development of acute acalculous cholecystitis.