CATABOLISM OF LOW-MOLECULAR-WEIGHT HYDROXYETHYLATED AMYLOPECTIN IN MAN .1. CHANGES IN THE CIRCULATING MOLECULAR COMPOSITION

  • 1 January 1979
    • journal article
    • research article
    • Vol. 94  (6) , 841-847
Abstract
Intravascular persistence concomitant with changes in the circulating molecular composition were determined in 6 fasted normal men dosed with 400 ml of 14% LMW-HES (low MW hydroxyethylated amylopectin, a new plasma expander). The concentration of LMW-HES in serum fell to half its peak value in 3.9 .+-. 1.1 (SD) h, but serum levels of glucose remained elevated throughout the 12 h postinjection fasting period. The LMW-HES recovered from the intravascular space was shown by gel filtration on a column of Sepharose CL-4B to be of a narrower molecular size distribution (less polydispersion) than in the injected material. The ratio of Kav [average equilibrium constant] .cntdot. urine/Kav .cntdot. injected solution was 1.34. At 30 min after injection, the ratio of Kav .cntdot. urine/Kav .cntdot. serum was 1.20, and by 24 h the value was 1.15. Changes in the molecular distribution in the bloodstream between the end of the infusion period and 24 h later were small. The intravascular catabolism of LMW-HES may occur in 2 distinct phases: a rapid initial degradation, followed by a more gradual elimination influenced by the MS [molar hydroxyethyl group substitution on the parent amylopectin molecule] of the injected material.