Fig. 5. Effect of repeat bladder distension at 60 mmHg for 20 s every 4 min after pretreatment with intravenous ketamine (3 mg/kg) or normal saline on reflex responses to urinary bladder distension (UBD). (A ) Change in mean arterial blood pressure (ΔMAP) after saline (n = 44) and ketamine (n = 8); (B ) abdominal electromyographic activity evoked by repeated UBD after same pretreatments (saline, n = 31; ketamine, n = 8). Data are mean ± SEM.