Fig. 5.

Effects of nonuniform [Ca²⁺]_i and contraction on the aftercontractions (F_CW) and [Ca²⁺]_i (Ca_CW) during the aftercontractions with the regional increase in [K⁺]_o in the absence of Isoproterenol. A and B, top 2 panels: amplitudes (ΔF_CW) and intervals of the F_CW. A and B, bottom 2 panels: amplitudes (ΔCa_CW) and intervals of the Ca_CW. C and D, top 2 panels: propagation velocity of Ca²⁺ waves. C and D, bottom 2 panels: the ΔCa_CW and the intervals of the Ca_CW. Black and gray symbols indicate the changes with (R) and without the regional increase in [K⁺]_o (C), respectively. *P < 0.05 vs. C; #P < 0.01 vs. C (paired t-test). A: effect of the regional increase in [K⁺]_o on the F_CW and Ca_CW in the presence of both 3 μmol/l SEA0400, an Na⁺-Ca²⁺ exchange blocker, and 10 μmol/l cilnidipine, an L/N-type Ca²⁺ channel blocker (n = 6). B: effect of the regional increase in [K⁺]_o on the F_CW and Ca_CW in the presence of 100 μmol/l streptomycin, a stretch-activated channel blocker (n = 7). C: effect of the regional increase in [K⁺]_o on the propagation velocity of Ca²⁺ waves and Ca_CW in the presence of 20 mmol/l 2,3-butanedione monoxime (BDM) (n = 5). D: effect of the regional increase in [K⁺]_o on the propagation velocity of Ca²⁺ waves and Ca_CW in the presence of 10 μmol/l blebbistatin (n = 5).