Figure 6

Ritanserin induce caspase activity in COS. a: Effects of serotonin, and ritanserin on caspase activity in COS. Caspase activity increased with escalating concentrations of ritanserin, with mildly increased activity appreciated at 3.125 (p = 0.0170) and 12.5 μM (p = 0.025) and markedly increased activity present with 25.0 and 50.0 μM (p < 0.01). No difference in caspase activity between the DMSO vehicle control and any concentration of serotonin were observed. Concurrent incubation of ritanserin with 12.5 μM serotonin showed attenuated caspase activity at 3.125 (p = 0.049) and 6.25 μM ( p = 0.043) ritanserin relative to cells treated with ritanserin alone. Caspase activity in taurolidine treated cells, the positive control, was significantly greater than the vehicle control (p < 0.01). Plotted values are mean caspase activity +/− 95% confidence interval of mean. b: Caspase activity in COS treated with ritanserin in the presence or absence of a caspase inhibitor. Pre-incubation with the general capase inhibitor Z-VAD-FMK dramatically decreased caspase activity in COS cells treated with 12.5 μM ritanserin (p < 0.01). Plotted values are mean caspase activity +/− 95% confidence interval of mean.