Membrane stress increases cation permeability in red cells.

AUTOR(ES)

Johnson, R M

RESUMO

The human red cell is known to increase its cation permeability when deformed by mechanical forces. Light-scattering measurements were used to quantitate the cell deformation, as ellipticity under shear. Permeability to sodium and potassium was not proportional to the cell deformation. An ellipticity of 0.75 was required to increase the permeability of the membrane to cations, and flux thereafter increased rapidly as the limits of cell extension were reached. Induction of membrane curvature by chemical agents also did not increase cation permeability. These results indicate that membrane deformation per se does not increase permeability, and that membrane tension is the effector for increased cation permeability. This may be relevant to some cation permeabilities observed by patch clamping.

Documentos Relacionados

• Oxidant stress activates a non-selective cation channel responsible for membrane depolarization in calf vascular endothelial cells.
• Ionic permeability of, and divalent cation effects on, two ATP-gated cation channels (P2X receptors) expressed in mammalian cells.
• Increased Erythrocyte Cation Permeability in Thalassemia and Conditions of Marrow Stress
• Rotavirus nonstructural glycoprotein NSP4 alters plasma membrane permeability in mammalian cells.
• Differential effects of temperature on three components of passive permeability to potassium in rodent red cells.