Herbert C. Tidwell

The intravenous administration of fat

Summary 1. It is possible to prepare fat emulsions that can safely be administered by vein. 2. Our experience confirms that of others, suggesting that these preparations are of value in parenteral feeding. 3. The possible limitations of their use are discussed.

Lipid absorption: palmitic acid-1-C13 and tripalmitin-carboxyl C14.

Palmitic acid-1-C13 and tripalmitin-carboxyl C14 dissolved in olive oil were administered orally to previously fasted rats. The animals were sacrificed at 1, 2 and 3 hours after the administration of the doubly labeled lipid and the lipids were recovered separately from the stomachs and small intestines. The presence of each isotope in the lipid-fed and in that recovered was measured. The intestinal lipids showed a marked decrease in the excess of C13. The C14 label was considerably reduced in specific activity, but not to a comparable extent. The data appear best explained by a combined process of selective absorption of the free fatty acids and dilution with endogenous lipids. When C13- and C14-labeled palmitic acids were administered to an animal to determine whether any isotope effect might influence the results, a decrease in isotope content was observed; however, no change occurred in the ratio of the two isotopes.