Low concentrations of mercury induce changes in ion composition of cultured myoblasts

The effects of low concentrations (1 pM, 1 nM, 1 microM) of mercuric chloride on ion distribution in cultured myoblasts were analysed by energy dispersive X-ray microanalysis. An increase in intracellular sodium concentration was observed five minutes after addition of HgCl2 to the culture medium. This increase was dose dependent and accompanied by a transient decrease in potassium concentration. Exposure to 1 nM and 1 microM HgCl2 led to a two-fold increase in the cytoplasmic chlorine concentration. The higher HgCl2 concentration (1 microM) induced morphological alterations in the form of cell membrane blebs, perforations and shrinkage or flattening of the myoblasts. It was concluded that even low concentrations of mercuric chloride cause elemental and morphological changes in cultured myoblasts, which may reflect effects of the metal on membrane permeability.