Unesterified Fatty Acids and Lipid Transport in Dogs.

Abstract
Plasma neutral fats and unesterified fatty acids were investigated in different conditions of increased lipid transport in the dog. During fat absorption, in addition to the increase in neutral fats, unesterified fatty acid also increased. Heparin and protamine influenced both transport mechanisms in the post-absorptive state, the former increasing the unesterified fatty acids and decreasing the esterified fatty acids; the latter opposing this effect. Starvation for 48-72 hours and acute CCll4 poisoning raised the unesterified fatty-acid level markedly. The results indicated the metabolic importance of unesterified fatty acids in lipid transport and the possible role of clearing factor in regulating lipid metabolism.