Relationship between the Alteration of Lipid Fraction of Erythrocyte Membrane and the life Span of Erythrocyte in Uremics

Abstract

The purpose of the present investigationn was to elucidate the mechanism of shortened life span of erythrocyte through the observations of chemical and physical properties of the erythrocyte membrane obtained from uremics. The results of this investigation were obtained as follows.(1) The life spann of erythrocyte measured by using Cr⁵¹ was revealed to be shorter than that of normal subject.(2) Serum phospholipid and lysophosphatidyll choline were decreased, but serum phosphatidyl ethanolamine was increased inn uremics.(3) The membrane cholesterol content was normal, but the phospholipid was decreased, conse-quently the ratio of cholesterol to phospholipid was significantly elevated. The elevated ratio of cholesterol to phospholipid seemed to reflect the alteration of membrane composition. (4) In the phospholipid fraction, the membrane phosphatidyl serine was markedly decreased, (5) The content of the erythrocyte ATP was elevated but, on the contrary, the (Mg²⁺+Na⁺+K⁺)-dependent ATPase activity indicating the actual utilization rate was markedly decreased.(6) Increasing activity of ATPase of erythrocyte stroma was parallel with the additive concentration of phosphatidyl serine in vitro.