Deformability of mammalian and fish erythrocytes: comparison of mean pore transit times of cells and estimation of cellular viscosity and elasticity.

Abstract

Red blood cells (RBCs) of various species of mammals and fish were subjected to a modified Nuclepore filtration test, which determines average time required for cells to pass through filter pores under constant suction. The values so far obtained, when plotted against the ratio of mean cell diameter to pore diameter, fall in a region given by a formula, which has been derived from a simple viscoelastic model for the deformation of a cell, for a small range of cellular viscosity (1.0-2.0 x 10(3) dyn.s/cm for mammals at 37 degrees C, 3.0-5.0 x 10(-3) dyn.s/cm for fish at 15 degrees C). Furthermore, estimates of cellular elasticity given from pore transit times at the cell-pore diameter ratio beyond 2.0 also fall in a similar range (0.5-1.0 dyn/cm) for both the mammalian and fish cells. It is thus suggested that RBC filterability may not differ greatly, when compared at a comparative temperature, between different species studied so far, including mammals and fish, for a relatively large range of the extent to which cells are caused to deform. A question then arises about the shape and cytoplasm factors which have been accepted as the primary determinants of RBC deformability.