Affiliations: [a] Department of Neurology, Oregon Health Sciences University, Portland, Oregon 97201 | [b] Veterans Administration Medical Center, Portland, Oregon 97201 | [c] Department of Surgery, Oregon Health Sciences University, Portland, Oregon 97201 | [d] Department of Neurology, Hua Shan Hospital, Shanghai 200040, People’s Republic of China
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Note: [] Accepted by: Editor H. Meiselman
Abstract: The fragility of erythrocytes (RBC) from patients with acute ischemic stroke and from normal age-matched control individuals was compared in the presence of ionomycin and various calcium ion concentrations ranging from 0 to 2.5 mM after filtration through 5 µm pore diameter polycarbonate membranes at 20 cm Hg pressure. At calcium ion concentrations of 0.5, 1.0 and 1.5 mM, RBC from stroke patients hemolyzed to a greater extent than those obtained from controls. This difference is indicative of abnormal calcium ion homeostasis in RBC obtained from stroke patients. Flunarizine, a calcium ion channel blocker, significantly inhibited the degree of hemolysis of RBC due to calcium loading in both stroke and control groups. These data are consistent with numerous reports showing that calcium ion homeostasis plays a crucial role in governing RBC mechanical properties including cellular deformability.
