Abstract: OBJECTIVE: To observe the changes of liver function and ultrastructures induced by trichloroethylene in sensitized guinea pigs. METHODS： White female guinea pigs (250-300 g) were randomly divided into blank control group， solvent (olive oil) control group and TCE treatment group. Guinea pigs were treated with guinea pig maximization test (GPMT). Specimens were collected at 24 h and 72 h after last stimulation， liver tissue pathology and ultrastructures examined，and AST，ALT，TP，ALB，GLB and A/G in serum measured. RESULTS： Sensitization rates were 65.38% in TCE treatment groups. Compared with TCE sensitized 24 h group and TCE non-sensitized 72 h group， ALT and AST levels in TCE sensitized 72 h group increased significantly(P<0.05). Compared with solvent group and TCE non-sensitized 72 h group， ALB levels in TCE sensitized 72 h group increased significantly(P<0.05). TCE sensitized group 72 h revealed more edema in liver cells with nucleus ruptured and disintegrated. TEM observation showed： a few mitochondria vacuoles， degeneration， rough endoplasmic reticulum decreased in TCE non-sensitized group. TCE sensitized group demonstrated reduction in the number of mitochondria in liver cells， rough endoplasmic reticulum fracture， expansion， decreased glycogen granules. In the group of 72 h after the last challenge，more serious damage was visible than those in 24 h group. CONCLUSION： Liver dysfunction and ultrastructural damage occurred in sensitized guinea pigs induced by trichloroethylene. The extent of injury gradually increase with time.

Key words: trichloroethylene, guinea pigs, liver, injury