The Effect of Pelvic Nerve Stimulation

The aim of the study was to investigate the effect of electrical pelvic nerve stimulation (PNS) on recto-anal motility. The response to PNS was investigated in 8 alpha-1-chloralose anaesthetized pigs. Anal and rectal pressure and rectal cross sectional area (CSA) were recorded by manometry and impedance planimetry, respectively. A new probe design allows measurements of CSA at 5 different locations in the rectum and anal pressure simultaneously. Low intensity PNS (2 times threshold) resulted in a decrease of anal pressure (n=5) and an increase of anal pressure (n=3). High intensity PNS (5 times threshold) resulted in a decrease of anal pressure (n=8). The rectal motility response to PNS showed an increase of CSA near the anal canal and a reduction of CSA in the oral part of the rectum. The results confirms anal motility responses to graded PNS seen in other species. Furthermore, a dual pelvic nerve influence on the rectum was demonstrated with the new probe design