Role hepatic interstitial albumin in regulating albumin synthesis

Abstract

An extravascular osmotic regulatory system possibly controlling albumin synthesis has been postulated. Albumin metabolism and interstitial hepatic albumin were measured in control and dextran-treated rabbits. Hepatic interstitial albumin was determined from the difference (obtained simultaneously) between total hepatic albumin, and hepatic plasma albumin (albumin-I125) in eight control rabbits and nine rabbits receiving 1.5 g of dextran (avg mol wt, 188,000) for 2-3 weeks. Hepatic extracellular volume (sucrose-C14) and plasma volume (albumin-I131) were determined in 15 control and in 15 dex-tran-treated rabbits. Following dextran, albumin degradation fell from 273 to 217 mg/kg per day, body albumin pool decreased 21%, serum albumin fell from 3.6 to 2.4 g/100 ml. Hepatic interstitial albumin rose from 27 [plus or minus] 6 (SE) mg to 52 [plus or minus] 6 mg/100 g wet liver weight. Hepatic interstitial volume was unaltered by dextran. Albumin synthesis varied inversely with interstitial albumin and the data are consistent with the hypothesis that albumin synthesis may be sensitive to albumin concentration within the hepatic interstitial space.