Effect of SKI3246 on upper gastrointestinal (GI) transit time of guinea pigs. (A) Effect of SKI3246 on upper GI transit time of guinea pigs in the native condition (n = 6). SKI3246 had no effect on charcoal transit time at 3 dose levels as compared with the control group by Mann-Whitney test. (B) Effect of SKI3246 on upper GI transit time in TRH-pretreated guinea pigs (control groups, n = 6; TRH pretreatment control groups, n = 5; SKI3246 treated groups, n = 7). Guinea pigs pretreated with TRH (100 μg/kg) showed no difference in charcoal transit compared with the control group. As compared with the control group, SKI3246 showed no effect on charcoal transit at 3 different dose levels among groups pretreated with TRH. (C) Effect of SKI3246 on upper GI transit in mustard oil (MO)-pretreated guinea pigs (control groups, n = 6; MO pretreatment control groups, n = 5; SKI3246 treated groups, n = 7). Groups pretreated with MO (10 mg/kg) displayed significantly elongated charcoal transit compared with the control group (P = 0.009). Among MO-pretreated groups, SKI3246 had no effect on charcoal transit at lower doses compared with control group. At a higher dose (600 mg/kg), however, SKI3246 significantly shortened the charcoal transit (P = 0.030). The error bars indicate standard deviation.