The formation of electrical excitability in cultured frog embryonic myocytes

Quantitative changes of sodium and potassium ionic currents were studied in the frog embryonic skeletal myocytes cultures under conditions preventing cell fusion and division. During 7 days of culturing the mean values of the sodium and potassium currents densities were 7- and 1.8-fold increased, resp. In currents clamp records the APs were observed only after 5 days of culturing, and in cells with proportion of sodium and potassium conductances above the critical level.