Increased plasma and aortic triglycerides in rabbits after acute administration of 2,3,7,8-tetrachlorodibenzo-p-dioxin.

Administration of a single nonlethal dose (20 micrograms/kg) of 2,3,7,8-tetrachlorodibenzo-p-dioxin to New Zealand male rabbits, both on a standard and on a cholesterol (0.5% in the diet) regimen, resulted in a significant increase of plasma triglyceride levels. Triglycerides were particularly raised in the very low-density lipoprotein fraction; no significant apolipoprotein changes, as assessed by an analytical isoelectrofocusing procedure, could be determined. Concomitant to the increased triglyceridemia, aortic triglycerides were also significantly elevated in 2,3,7,8-tetrachlorodibenzo-p-dioxin-pretreated rabbits, both on the standard and on the cholesterolemic regimen. These findings suggest that 2,3,7,8-tetrachlorodibenzo-p-dioxin, possibly by inhibiting triglyceride breakdown, may induce an atherogenic form of hypertriglyceridemia in a standard experimental model of atherosclerosis.