Fig. 4
Effects of small- and intermediate-conductance Ca2+-activated K+ channel blockers on 5-HT-induced coronary response. In LNAME-treated hearts: a5-HT-induced coronary flow increases were significantly suppressed by TRAM-34, which is a selective blocker of intermediate-conductance Ca2+-activated K+ channel. b In hearts treated with the selective blocker of small-conductance Ca2+-activated K+ channel UCL1684 3 μM, 5-HT elicited slight coronary flow increase at 1 μM; but compared to the control test, 5-HT-induced coronary flow increases were significantly suppressed. c Coronary flow responses to 5-HT were not significantly altered after re-equilibration, prolonged perfusion with L-NAME, and repeated treatments of vehicle (DMSO 100 μl/dl). Data were expressed as the mean ± SD. #P < 0.05, ##P < 0.01, and ###P < 0.005 compared to the treatment (one-ways ANOVA followed by Bonferroni post-test). ƗƗƗP < 0.005 compared to the control group; &&&P < 0.001 between the compared groups (2-ways ANOVA followed by Bonferroni post-test)