Reversible Effects of Lysolecithin on Fusion of Cultured Rat Muscle Cells

Lysolecithin prevented the natural cell fusion in monolayer cultures of rat leg muscle cells when it was added in the range of 120 to 160 μg/ml of complete growth medium. The cells rapidly recovered the ability to fuse after withdrawal of the lysolecithin medium and replacement by the regular growth medium. Lysolecithin prevented myogenic cell fusion within a narrow concentration range in the presence of sufficient concentration of calcium and pH values between 7.4 and 7.8. Comparisons between effects of lysolecithin, high cyclic-AMP and low calcium-containing media on cultures of muscle cells were also made. The elaboration of long, thin processes from the bipolar ends of myogenic cells was a feature particularly noticeable with lysolecithin and cyclic-AMP-containing culture plates. The possible influences of other, non-specified, natural surfactants, reacting with lipoprotein micelles of the plasmalemma and subsequently affecting the orientation and arrangement of cell boundaries during differentiation of various cell types, are discussed.