Abstract
In western countries, left-sided diverticular disease (LDC) is very common, but right-sided diverticular disease (RDC) is rare. On the other hand, in Oriental countries including Japan, RDC is more common than LDC. In the pathogenesis of diverticular diseases, RDC has been considered among those diseases with anomaly of colonic motility. It is well known that the genesis of pressure-induced diverticula related to the increased tension which causes blow-out of the mucosa in the colon haustrum located between two successive segments of spastic circular muscle (i.e., colonic segmentation). Peristalsis is very important in the transport of intestinal contents from the mouth to the anus and is mainly controlled by the enteric nervous system (ENS). Physiological, pharmacological and histochemical investigations have indicated that non-adrenergic, non-cholinergic (NANC) excitatory and inhibitory nerves, in addition to adrenergic and cholinergic components, play an important role in the regulation of intestinal peristalsis. However, there have been few reports in regard to the physiologic function of the ENS in patients with diverticular disease. In particular, physiologic functional differences of the ENS between the RDC and the LDC remain unknown. Recently, it has been reported that the ENS contains excitatory and inhibitory nerves and that the former, especially cholinergic nerves, are dominant in both RDC and LDC. Furthermore, there are no functional differences of the ENS between the RCD and LDC. These observations may be related to the high intraluminal pressure due to colonic segmentation in colonic diverticular disease, including RCD and LDC.
