[Elasticity of the erythrocyte membrane: overview and attempted explanation based on recent data on the ultrastructure of the membrane skeleton].

Membrane shear elasticity enables the mammalian erythrocyte to reassume its discoid shape after traversing narrow constrictions of the microcirculation. Both the high extensibility of the erythrocyte membrane under shear and its positive heat of deformation represent special features of its elastic response, which are poorly understood as yet. Following an introductory outline of the conceptual framework and ultrastructural basis of erythrocyte membrane shear elasticity, an attempt is made to explain qualitatively the strange deformation behaviour of this membrane in terms of present day knowledge on the molecular arrangement and performance of the major erythrocyte membrane protein, spectrin.