Rapid in vitro screening model for drugs affecting calcium ion mediated erythrocyte mechanical fragility

Abstract

A novel rapid in vitro screening model for testing the effects of pharmacological substances on calcium ion mediated mechanical fragility of human erythrocytes is presented. Red cells are rendered rigid and mechanically fragile by calcium ion loading of human erythrocytes via the ionophore A23187. The cells are then filtered through 5 µm pore diameter polycarbonate filter membranes at 20 cm Hg pressure. In contrast to normal cells the rigid and mechanically fragile cells are impeded at the surface of the filter and tensions exceeding the material strength of the red cell membrane develop resulting in hemolysis. The extent of hemolysis in the filtrate, which can be inhibited dose-dependently by the rheoactive calcium channel blocker flunarizine, is then assayed. The model lends itself as a primary screening method for discovering and developing pharmacological agents potentially useful in the treatment of ischemic vascular diseases.