We have previously demonstrated that the major propulsive motor pattern
in the rabbit colon, the colonic motor complex, manifests itself in
different motor pattern configurations depending on the level of
excitation of the colon. In the rabbit, intraluminal prucalopride, in a
dose dependent manner, evoked several motor patterns starting with fast
propagating contractions (45) that result in simultaneous pressure waves
(39) to the most forceful propulsive contraction, the Long Distance
Contraction (LDC), that results in high-amplitude propagating pressure
waves (39), similar to the HAPW reported here. The rabbit study and the
present study suggest that SPWs and HAPWs are part of the repertoire of
propulsive activities in the human colon and that the SPWs are generally
evoked at lower levels of excitation.
The HAPW is an essential component of the process of defecation and
patients with constipation tend to have fewer HAPWs (16) (4, 40) (23).
Reduction in occurrence of HAPWs can be accompanied by a decreased
frequency of urge to defecate (34). Consistently, some patients with
diarrhea-predominant irritable bowel syndrome (IBS-D) have been observed
to generate more HAPWs compared with healthy subjects (25). Data
reported here, indicate that luminal prucalopride can act as an
effective prokinetic. Its effect appears to be similar to that of oral
prucalopride (13).