Quantitative Analysis of Hemolytic Action of Lysophosphatidylcholines in Vitro: Effect of Acyl Chain Structure

Abstract

Hemolysis of rabbit erythrocytes by several lysophosphatidylcholines (lysoPCs) containing C₁₂-C₁₈ saturated and cis unsaturated acyl chains was investigated in vitro. The degree of hemolysis was dependent on the erythrocyte concentration used.Based on this dependency, two determinants for the drugs'hemolytic activity, namely, their affinity for the cell membrane and their intrinsic hemolytic activity, were analyzed separately to clarify the relationship between these factors and the acyl chain structure. Elongation of the acyl chain in saturated lysoPCs was found to greatly increase the affinity and slightly increase the intrinsic activity. In contrast, the introduction of a cis double bond into the acyl chain was found to slightly decrease the affinity and to significantly decrease the intrinsic activity. The affinity and the intrinsic hemolytic activity are discussed in relation to critical micellar concentration and bilayer solubilization ability, respectively.