Factors of the shape change of human erythrocytes induced with lidocaine.

We studied the molecular mechanism of the shape change of erythrocytes with a local anesthetic, lidocaine. The shape of human erythrocytes changed from discocytes to stomatocytes in the presence of lidocaine when ATP was present. But, the shape of resealed cells which were prepared with 10 mM Tris-HCl buffer (pH 7.4) containing 2 mM ATP-MgCl2 and various substances was not changed from discocytes to stomatocytes with lidocaine. When intact cells and resealed cells which were prepared with various concentrations of Tris-HCl buffer (pH 7.4) were incubated with various concentrations of lidocaine and their membrane proteins were analyzed by SDS-PAGE, the densities of bands 62K, 28K and 22K depended on lidocaine concentration: in particular, that of band 28K changed remarkably. These membranous 62K-, 28K- and 22K-proteins agreed with cytoplasmic 62K-, 28K- and 22K-proteins in molecular weight. We propose that not only ATP but also the 62K-, 28K- and 22K-proteins in the cytoplasm are concerned with the shape change of human erythrocytes induced with lidocaine.