Abstract
Non-ionic surfactant of polyoxyethylene derivatives was dissolved in 0.9% sodium chloride solution and this solution was injected into the femoral region of a rabbit to observe its local irritating action to the muscle by naked eyes. The appearance of the muscle at 24 hours after the injection would enable compare the local action of surfactants. The higher the concentration of the surfactant and the more number of injections, the severer the action was. From the structure of the surfactants, the local action became weaker as the degree of polymerization of oxyethylenes was increased or hydrophilic property is raised Moreover, in respect to the shape of the surfactant molecules, the broad molecules caused the weaker local action than the narrow and long molecules. Microscopic observation of the cross-sections of muscles under such a local action showed that in portions with drastic local action degeneration of cytoplasm occured by destruction on the other hand, of cell membrane of muscle fiber cells in the portions with weak action healthy cells remained. The local action of the surfactants was found to be in parallel with their hemolytic action and it was assumed that the mechanism of this local action was similar to that of their hemolytic acition, that is, penetration of the surfactant into cholesterol of the cell membrane. Therefore, penetration of surfactants into monomolecular layer of cholesterol was measured and this was found to agree with the above tendency.
