Abstract
We previously reported that the feeding of the safflower oil diet results in lower acetyl-CoA carboxylase activity in the liver compared with the feeding of a beef tallow diet. We also suggested that sympathetic activity (norepinephrine turnover rate and α1-adrenergic receptor binding) in the liver was higher in the safflower oil diet group. In order to confirm the effect of dietary fats consisting of different fatty acids on the hepatic acetyl-CoA carboxylase activity related to sympathetic activity, we chemically sympathectomized rats by treating them with 6-hydroxydopamine. The sympathectomized rats and control rats were then meal-fed a safflower oil diet or a beef tallow diet for 8 weeks. Sympathectomy abolished the difference in acetyl-CoA carboxylase activity in the liver between the two dietary groups. The percentage of body fat was increased by sympathectomy, resulting in no difference between the safflower oil diet group and the beef tallow diet group. These results support the hypothesis that, the intake of a safflower oil diet decreases hepatic acetyl-CoA carboxylase activity by increasing the sympathetic activity.
