OBJECTIVE: In order to improve insights in rectal filling sensation, we studied pouch filling sensations after ileal J pouch-anal anastomosis (IPAA) before and after re-establishment of bowel continuity. METHODS: Anal manometry and a pouch filling sensation test were performed before as well as 1 and 6 weeks after closure of the loop ileostomy in 17 patients who had undergone restorative proctocolectomy with stapled (8 patients) or manual pouch-anal anastomosis (9 patients). The results were compared with those of 12 control subjects. RESULTS: Before ileostomy closure, pouch pressure necessary for inducing the respective sensation thresholds was higher than in controls; the difference was significant for constant and urge sensation. The volumes for urge and maximum tolerable sensation level were significantly lower, with reduced pouch compliance. After stoma closure, pressure and volume thresholds at all sensation levels became completely comparable with control data. No relevant differences were observed between stapled and manual ileal pouch-anal anastomoses. CONCLUSIONS: All levels of filling sensation levels are preserved after restorative proctocolectomy and their parameters are comparable with those of normal rectal filling sensation. Diversion of an ileal J pouch results in resetting of filling sensation thresholds towards lower volume and higher pressure values, but all sensation thresholds normalize within 6 weeks after stoma closure. These data document that neither the rectum, nor the mucosa of the anorectal junction and upper part of the anal canal are involved in filling and urge sensation.