Fig. 2

The high K⁺-induced Ca²⁺ transient is sensitive to L-type Ca²⁺ channel modulators. a The bath contained 1.2 mM Ca²⁺ to highlight the effect of the agent. Left Application of a 150 mM K⁺ solution caused a small increase in fluo-3 fluorescence. Right In the presence of FPL-64176, fluo-3 fluorescence was markedly increased upon exposure to the high K⁺ solution. b Left In the absence of nitrendipine, application of a 150 mM K⁺ solution evoked a transient increase in fluo-3 fluorescence. The bath contained 2 mM Ca²⁺. Right In the presence of 1 µM nitrendipine, exposure to the high K⁺ solution failed to increase fluo-3 fluorescence