Abstract: Objective: To investigate the effect of tea-seed oil on serum lipid metabolism and atherosclerosis (AS) formation. Methods: Totally 32 New Zealand rabbits were randomly divided into four groups. The rabbits in the control group were fed with normal diet and those in other three groups were fed with three kinds of high cholesterol diets containing tea-seed oil, peanut oil and olive oil, respectively, for 2 consecutive months. The serum lipid in each group was measured at 0, 1 and 2 months. At the end of the experiment, all animals were sacrificed and the aorta, heart and liver were harvested for histological examination. The morphological change was observed and the atherosclerosis status was measured by using Image-pro plus software. Results: The serum lipid levels in three experiment groups were significantly higher (P＜0.01) than that in the control group. The levels of triglycerides (TG), cholesterol (TC) and low-density lipoprotein (LDL) in the tea-seed oil group were lower than those in the peanut oil group, but there was no significant difference (P＞0.05) between these indices. Morphological observations revealed atherosclerosis formation in coronary artery and aorta in the three experiment groups. The aortic intimal hyperplasia and atherosclerotic plaque in the peanut oil group were larger than those in the tea-seed oil and olive oil group. The aortic stenosis rate in the peanut oil group was 35%－70%, whereas only 5%－15% in the tea-seed oil group and olive oil group. In addition, the most serious hepatic steatosis was observed in the peanut oil group. The vacuolar change in liver cells clearly showed a pathological feature of moderate fatty liver, but a slight change in pathological feature observed for the tea oil and olive oil groups. Conclusion: Tea-seed oil can inhibit therosclerosis and hepatic steatosis induced by high fat diet, which displays the same pharmaceutical effect as olive oil.

Key words: tea-seed oil, fatty liver, atherosclerosis, serum lipid