Figure 6

K⁺-dependent development of window contraction. Isometric contractions induced by addition of 3.5 mM Ca²⁺ to 0Ca containing 10 up to 124 mM K⁺ (A). Absolute (B) and relative (50 mM K⁺ set to 100%, C) [K⁺]-force curves were determined at 200, 400 and 600 s (see dotted lines in A), were bell-shaped and could only be fitted up to 50 mM K⁺ (B, C). Results show mean ± s.e.m, n = 6. *, **, ***: P<0.05, 0.01, 0.001 versus 50 mM K⁺.