Morphology of Myenteric Plexuses in the Human Large Intestine

Abstract

Large intestines with diverticula exhibit functionally abnormal peristaltic activity and elevated luminal pressure that may indicate functional changes in the myenteric plexus; however, no studies have investigated the characteristics of either normal or diverticula myenteric plexuses. Tissue specimens obtained from 93 colorectal cancer patients without diverticula, 14 patients with perforated diverticulitis, and 12 colorectal cancer patients with asymptomatic diverticula were included in this study. Myenteric plexuses and ganglion cells were counted per centimeter, and the area and maximum diameter of the nuclei of ganglion cells were measured using an image analyzer. The number of myenteric plexuses and ganglion cells per centimeter was significantly higher in the descending colon, sigmoid colon, and rectum than in the cecum, ascending colon, and transverse colon. The area of the nuclei of ganglion cells was significantly larger in the descending colon and sigmoid colon than in the cecum and ascending colon. Compared with large intestines without diverticula, the number of myenteric plexuses was significantly higher in large intestines with diverticula, whereas the number of ganglion cells decreased in both right-sided and left-sided large intestines with perforated diverticulitis or asymptomatic diverticula. The area of the nuclei of ganglion cells was significantly smaller in large intestines with diverticula. The morphology of myenteric plexuses and the ganglion cells differs significantly among segments of the human large intestine. Large intestines with diverticula had significantly more plexuses but significantly fewer ganglion cells than large intestines without diverticula. The area of the nuclei of ganglion cells was also significantly smaller in large intestines with diverticula. Further studies are required to clarify how these changes are related to intestinal function and how they are involved in the etiology of diverticulosis.