Mechanical Stresses in Erythrocyte Membranes (Theoretical Models)
The type of mechanical stresses in the membranes of red blood cells caused by the effects of catecholamines and steroid hormones is discussed. Tensors of mechanical stresses and displacement in the membrane during its interaction with hormones are obtained. A possible mechanism of membranes rupture under mechanical stresses is discussed. Under the action of catecholamines and androgens microviscosity of membranes increases, in lipid membrane bilayer the alternating kink and stretching sites (resembling a "chessboard") appear. The membrane thickness at stretching site becomes thinner ("smectic A - smectic C" transition). With further increase in tensile stresses when they exceed a certain critical value, the membrane could burst. Perhaps before disruption at the stretching site in the lipid bilayer there was a "gel phase Lp<sub>'</sub> - liquid crystalline phase L<sub>a</sub>" transition. The density of the lipid bilayer thus decreased, the pores are formed and then the formation of cracks occurred.