Figure 6. Effect of [Mg²⁺]_p on I_Ca with different [Ca²⁺]_p.

Currents were measured at a test potential of 0 mV in myocytes dialysed with 0.2 mm and 1.8 mm[Mg²⁺]_p at ∼1 nm, 100 nm and 300 nm[Ca²⁺]_p. Data are means and s.e.m., with the number of experiments indicated in parentheses. Asterisks (*) indicate significant changes of I_Ca between low (0.2 mm) and high [Mg²⁺]_p (1.8 mm).