[Lipopolysaccharide-induced apoptosis of rat hepatocyte in vitro].

OBJECTIVES: To investigate the effect of lipopolysaccharide(LPS) on hepatocyte in vitro. METHODS: The hepatocytes were isolated in the way of liver perfusion with 0.05% collagenase type I and type IV, and cultured for 24 h in vitro before LPS was added directly into the culturing medium. Propidium iodide(PI) staining, and transmission electron microscopy techniques had been used to observe the morphological changes of hepatocyte treated with LPS. DNA-fragment assay was analyzed by the agarose gel electrophoresis to determine apoptotic level. RESULTS: Hepatocytes incubated with LPS exhibited some typical apoptosis-specific morphological features. The DNA-fragment by agarose gel electrophoresis demonstrated the typical ladder pattern on the hepatocytes directly exposed to LPS, but it was absent in the group used ATA, an inhibitor of apoptosis. These morphological changes, accompanied by DNA fragmentation assay, confirmed that cells were dying through an apoptotic pathway. In addition, the hepatocyte number of apoptosis increased parallel with the dose of LPS and time within 24 h when hepatocytes were exposed to LPS alone. CONCLUSIONS: LPS can induce apoptosis of hepatocyte in vitro.