Metabolism of triacetin-derived acetate in dogs

Triacetin is a water-soluble triglyceride that may have a role as a parenteral nutrient. In the present study triacetin was administered intravenously to mongrel dogs (n = 10) 2 wk after surgical placement of blood-sampling catheters in the aorta and in the portal, hepatic, renal, and femoral veins. [1-¹⁴C]Acetate was infused to allow quantification of organ uptake of acetate as well as systemic turnover and oxidation. Systemic acetate turnover accounted for ≈ 70% of triacetin-derived acetate, assuming complete hydrolysis of the triglyceride. Approximately 80% of systemic acetate uptake was rapidly oxidized. Significant acetate uptake was demonstrated in all tissues (liver, 559 ± 68; intestine, 342 ± 23; hindlimb, 89 ± 7; and kidney, 330 ± 37 μmol/min). In conclusion, during intravenous administration in dogs, the majority of infused triacetin undergoes intravascular hydrolysis, and the majority of the resulting acetate is oxidized. Thus, energy in the form of short-chain fatty acids can be delivered to a resting gut via intravenous infusion of a short-chain triglyceride.