Relation of Hemolysis to the Primary Penetration of Fatty Acids Through the Red Cell Membrane.

Abstract

The hemolytic action of fatty acids may be attributed to the combined effects of injury of the erythrocyte at its surface and secondary penetration. It is obvious, however, that in high concentrations of the hemolytic agent, the damage to the membrane may in itself be sufficient to cause the dissolution of the cell, in which case the factor of permeability is of negligible importance. On the other hand, if the concentration is sufficiently low, the change in the red blood cell membrane may be so slight that a condition is approached in which primary penetration of the fatty acid may be regarded as the sole factor involved in the process.

That under certain conditions measurement of the rate of hemolysis also determines the rate of permeability of the hemolytic agent has been considered elsewhere 1 and is supported by the observation that the hemolytic action of fatty acids parallels their behavior in a wide variety of biological phenomena in which primary penetration of these acids into tissues is involved.

Another test of the osmotic nature of the process may be made by varying the tonicity of the hemolytic system. It has been shown previously 2 that increasing the osmotic concentration of the fluid outside the corpuscles has little effect in altering their resistance to the hemolytic action of inorganic acids, which makes it seem probable that injury to the membrane is the primary factor involved. On the contrary, alterations in the concentration of the outside fluid exert a marked effect in hemolysis by fatty acids, which indicates that here penetration into the corpuscle is the predominant factor. This is illustrated in the accompanying chart, which represents the relation of tonicity (expressed in per cent NaCl) to the resistance of dog's corpuscles to the hemolytic action of fatty acids.