| Abstract: | Abstract Cyclical motor activity of the gastrointestinal tract, normally occurring during the interdigestive period in several mammals, is disrupted in the post-operative ileus. We determined the recovery from the disappearance of cyclical motor activity, from the stomach to the colon, in dogs after laparotomy with the force transducers. Moreover, we examined the effects of Leu13-motilin (KW-5139) and prostaglandin F2a (PGF2a), administered in the early post-operative period, on the gastrointestinal motility. Following laparotomy, the cyclical motor activity reappeared firstly in the ileum and the colon, then in the jejunum and the duodenum, and finally in the stomach. The reappearance time of the phase III contractions in the stomach was 105.8 ± 10.6 h (n = 4). In the early postoperative period, KW-5139 (0.5 μg kg?1, i.v.) induced phase-III-like contractions, whereas PGF2a (50 μg kg?1, i.v.) induced simultaneously occurring contractions over the whole gastrointestine. The treatment with KW-5139 (0.5 μg kg?1, i.v.) four times (twice daily on the first and the second post-operative day) significantly (P < 0.05) shortened the time required to recover the phase III contractions in the stomach (64.2 ± 2.2 h, n = 4), whereas that with PGF2a (50 μg kg?1, i.v.) four times did not (111.3 ± 17.2 h, n = 4). The present results indicate that, after laparotomy, the cyclical motor activity recovers faster in the distal intestine than in the proximal intestine and the stomach, and that KW-5139, but not PGF2a, shortens the reappearance time of the phase III activity in the stomach. |
