ALBUMIN SYNTHESIS RATES MEASURED WITH [(2)H(5)RING]PHENYLALANINE ARE NOT RESPONSIVE TO SHORT-TERM INTRAVENOUS NUTRIENTS IN HEALTHY HUMANS

The response of albumin synthesis rates to infusion of either an intra venous nutrient mixture containing adequate nitrogen and energy or an isotonic saline infusion was compared in adult men. In a crossover stu dy, nine healthy male subjects received a shortterm (13.5-h) infusion of either the nutrient mixture or the saline solution, and albumin syn thesis rates were measured by a stable isotope technique employing [(2 )H(5)ring]phenylalanine. Fractional rates of albumin synthesis did not differ significantly between treatments (saline, 7.3 +/- 1.0%/d; intr avenous nutrients, 7.8 +/- 1.0%/d). The secretion time of albumin was significantly lower with intravenous nutrients infusion than with sali ne infusion. Plasma albumin concentration as well as prealbumin and tr ansferrin concentrations decreased over time when subjects were infuse d with either saline or the nutrient solution as a result of dilution rather than a change in synthesis. These results suggest that albumin synthesis rate does not respond to short-term intravenous nutrients.