Factors affecting liver uptake of serum free stearic acid-1-C14

Abstract

Hepatic extraction of intravenously injected albumin-bound stearic acid-1-C14 was studied in anesthetized rats. Hepatic C14 contents were nearly maximal within 4 min and, in young fed females, represented 47% of the injected label. By this time, about 98% of the stearate-1-C14 in the livers of all groups had been esterified and appeared chiefly in the phospholipids. Livers of large fed rats (500–600 g) and of 2-day fasted animals represented a smaller portion of body weight and acquired a lesser fraction of the injected stearate-1-C14 than did those of young fed controls. Subcutaneous epinephrine also reduced hepatic C14 incorporation. A single feeding of fasted rats with glucose or olive oil had no significant effect on C14 distribution. Contrary to inferences from several recent studies, there was no consistent relationship between serum free fatty acid level and the fraction of injected stearate-1-C14 appearing in the livers.