Myenteric nerve plexus in diverticular disease

Abstract

Although both the cause and the genesis of diverticular disease (DD) are unknown so far, the recent clinical, physiological, and pharmacological findings suggest that an abnormal cholinergic activity in the intestine smooth muscles initiates the uncomplicated form of the DD. The aim of the study was to assess the structural organization of the myenteric (Auerbach) nerve plexus (MNP) in the sigmoid colon from the DD patients and to compare it with the MNP in the sigmoid colon resected from patients operated on rectal tumors. Material and method: Samples of sigmoid colons about 10 cm in length from 10 patients with DD and 10 controls, underwent the sigmoid colon resections for rectal tumors, were fixed in 4% paraformaldehyde in 0.1 M phosphate buffer at 4°C for 2 hours and stained totally by histochemical method for acetyl- cholinesterase. Morphology of the MNP was assessed by the aid of a dissecting microscope, while digital images of the MNP were ana- lyzed on PC using the free available Image Tool software. Results: In contrast to controls, the MNP of the sigmoid colon in the DD was obviously atrophied, its interganglionic nerves – thinner and periodically interrupted. Ganglia of the MNP in patients with the DD contained the remarkably reduced neuronal number or/and nerve cells within myenteric ganglia were entirely negative for acetylcholinesterase. On average, the density of myen- teric ganglia in the same-sized area (25 mm 2 ) was significantly (P < 0.05) higher in controls compared with the DD patients (respec- tively, 163 ± 18 and 149 ± 11). Conclusion: Thickness of interganglionic nerves as well as the ganglion number and size in the sigmoid colon MNP in the DD are evidently decreased in respect of controls. Discussion: The results of this study demonstrate that the occur- rence of DD is associated with alterations in the MNP of the [...].