Effects of Chronic Renal Failure and Hemodialysis on Plasma Glomerulopressin

Abstract

Glomerulopressin (GP) is a small molecular weight hepatic hormone which increases glomerular capillary pressure and enhances glomerular filtration rate (GFR) in experimental animals. Protein ingestion, glucagon secretion and volume expansion raise plasma GP activity. Effects of end-stage renal disease (ESRD) and hemodialysis (HD) on GP activity are unknown. We measured plasma levels and HD clearance of GP in eight ESRD patients and four normals. Predialysis plasma GP in the ESRD group was significantly higher than in the control group (p < 0.01). Plasma GP activity was significantly lowered by HD (p < 0.01). GP activity of hemofiltrate averaged 38.1% of that in the predialysis plasma. Single passage through the dialyzer resulted in a significant fall in plasma GP activity (p < 0.001). Dialyzer clearance of GP was 143.8 ± 73.4 ml/min, representing 75.4% of that of urea. Conclusions: a) plasma GP activity is elevated in ESRD, due probably to increased production (volume expansion) and reduced renal elimination, b) GP is readily removed by HD and c) the fall in plasma GP postdialysis is due to removal by dialysis and possibly reduced hepatic release with the correction of hypervolemia.