Fig. 3

PP121 affected L-VDCCs, NSCCs, NCXs and potassium channels. A Treatment with 10 μM nifedipine, an L-VDCC-specific blocker, completely relaxed 80 mM K⁺-induced precontraction (n = 6/6 mice). B In the presence of 10 μM nifedipine, 100 µM ACh-induced precontraction during 2 mM calcium restoration was completely eliminated by 40 µM PP121 (n = 6/6 mice). C In the presence of 10 μM nifedipine, ACh-induced precontraction in 2 mM Ca²⁺ restoration was sequentially inhibited by 30 μM Pyr3, 30 μM gadolinium, and 40 μM PP121, while the average relaxant percentages of Pyr3, gadolinium, and PP121 are shown in (D) (n = 6/6 mice). E, F PP121 (40 μM) inhibited 100 μM ACh-induced precontraction in PSS or Li-PSS solution. G The bar graph shows the significant differences between the net forces of the baseline, contraction, and relaxation (n = 6/6 mice). H, I Treatment with 10 mM TEA or 1 μM PAX enhanced 100 μM ACh-evoked precontraction. The addition of 40 μM PP121 completely relaxed the precontraction (n = 6/6 mice)