ABSTRACT
Objective To investigate the effects and mechanisms of anal electrical stimulation (AES) with long pulses on anal sphincter pressure (ASP) in conscious dogs.Methods Nine healthy female hound dogs were used for the study,composed of 4 randomized sessions including AES with vari- ous stimulation parameters,20-min sustained AES to assess anal sphincter fatigue,atropine or phentolamine were used to block corresponding receptor.ASP was measured with manometry and the contractile area under the contraction curve.AES was performed via a pair of ring electrodes attached to the manometric catheter.The stimulation parameters in all sessions but the first session included a frequency of 20 ppm,width of 200 ms and amplitude of 3 mA.Results ASP was 55.7?6.0 at baseline and increased by 37% to 76.4?6.5 during AES (P