Effects of Dachengqi Decoction(大承气汤) on Morphological Changes in Enteric Nerve System of Rats with Multiple Organ Dysfunction Syndrome

Objective： To observe the morphological changes in enteric nerve system （ENS） of rats with multiple organ dysfunction syndrome （MODS） treated by Dachengqi Decoction （大承气汤, DCQD）. Methods： Fifty Wistar rats were randomly assigned to the control group, MODS model group and DCQD treated group. The rats in MODS model group and DCQD treated group were injected Escherichia coil （E. coli） suspension into abdominal cavity under sterile condition. The DCQD treated group was gavaged with DCQD 2 days before the E. coil suspension was injected. Twenty-four hours after injection, the proximal segment of intestine was resected and studied by immunohistofluorescence using vesicular acetylcholine transporter, vasoactive intestinal polypeptide （VIP）, substance P （SP） and neuronal nitric oxide synthase （nNOS） antibodies. The whole-mount preparations were observed by laser scanning confocal microscope to detect the changes of quantity and fluorescence integral optical density （IOD） value of intestine enteric nerves. Results： Compared with the control group, the quantity and IOD value of acetylcholine （ACh）, VIP, SP and nitric oxide （NO） nerves of intestine in the MODS group were significantly decreased （P〈0.01）, and the network of enteric nerves was remarkably disrupted. Compared with the MODS group, the quantity and fluorescence IOD value of ACh, VIP, SP and NO nerves in the DCQD group were significantly increased （P〈0.01）, and the network of enteric nerves was remarkably recovered. Conclusions： DCQD can protect and repair damage in the network of ACh, SP, NO and VIP nerves in rats with MODS, which may be one of mechanisms involved in promoting gastrointestinal motility by DCQD.

Characterization of smooth muscle, enteric nerve, interstitial cells of Cajal, and fibroblast-like cells in the gastric musculature of patients with diabetes mellitus

AIM To investigate histologic abnormalities in the gastric smooth muscle of patients with diabetes mellitus(DM).METHODS Full-thickness gastric specimens were obtained from patients undergoing surgery for gastric cancer. H&E stain and Masson's Trichrome stain were performed to assess the degree of fibrosis. Immunohistochemical staining using various antibodies was also performed [antibodies against protein gene product 9.5(PGP9.5), neuronal nitric oxide synthase(n NOS), vasoactive intestinal peptide(VIP), neurokinin-1(NK1) receptor, c-Kit, and platelet-derived growth factor receptor-alpha,(PDGFRα)]. Immunofluorescent staining and evaluation with confocal microscopy were also conducted.RESULTS Twenty-six controls and 35 diabetic patients(21 shortduration patients and 14 long-duration patients) were included. There were no significant differences in basic demographics between the two groups except in mean body mass index(BMI)(higher in the DM group). Proportions of moderate-to-severe intercellular fibrosis in the muscle layer were significantly higher in the DM group than in the control group(P < 0.01). On immunohistochemical staining, c-Kit- and PDGFRα-positive immunoreactivity were significantly decreased in the DM group compared with the control group(P < 0.05). There were no statistically significant differences in PGP9.5, n NOS, VIP, and neurokinin 1 expression. On immunofluorescent staining, cellularity of interstitial cells of Cajal(ICC) was observed to decrease with increasing duration of DM.CONCLUSION Our study suggests that increased intercellular fibrosis, loss of ICC, and loss of fibroblast-like cells are found in the smooth muscle of DM patients. These abnormalities may contribute to changes in gastric motor activity in patients with DM.

Improvement of mount preparations in showing myenteric nerve plexus from intestines of mice

Objective: The whole mount preparations of digestive tract is an effective experimental way to study the appearance and distribution of nerve plexus in digestive tract. Although myentric nerve plexus preparations technique was reported very early. But we have done experiment over and over during our research work in order to improve this traditional method and to meet the needs of our research work, we made some progresses in regular mount preparations after many experiments, which helped offer better situation in observing myentric nerve plexus. Methods: Five healthy male adult Kunming mice (20-30 g in weight) were used in this study. After intraperitoneal injection of muscle relaxant, with dislocation of cervical vertebra method, the abdominal cavity was exposed through abdominal median incision. After several steps of mount preparations the mucous layer and longitudinal muscle layer mount preparations with myentric nerve plexus were stripped under anatomical microscope. Immunohistochemical staining was also used in our study. Results: The mount preparation samples with myentric nerve plexus from intestines of mice showed positive SP immunoreaction. The positive cells were dark brown. Many of the cytons appeared circular and oval, while some appeared triangular or irregular. Conclusion: Our improved method is really a good method to show enteric nerve plexus. The method has many advantages and is particularly applied to small animals such as Kunming mice and BALB/c mice, weighing from 20 g to 30 g.

Morphological changes in interstitial cells of Cajal in the deep muscular plexus and enteric motor neurons of the intestine in rats with multiple organ dysfunction syndrome

BACKGROUND：Gastrointestinal motility dysfunction in multiple organ dysfunction syndrome （MODS） has been reported to be related to damage to interstitial cells of Cajal （ICC）. In the entedc nervous system, ICC and smooth muscle cells are connected in a network to form a special functional unit. Many gastrointestinal motility dysfunction diseases are associated with damage to this network.OBJECTIVE：To investigate the morphological changes of intestinal ICC, and to explore the mechanisms underlying gastrointestinal motility dysfunction in rats with MODS.DESIGN, TIME AND SE＇I-FING：The randomized, controlled, experiment was performed at the Central Laboratory of the First Affiliated Hospital of Dalian Medical University of China between June 2007 and March 2009.MATERIALS：Escherichia coli （E. colistrain O127 H6） and bovine serum albumin were purchased from Sigma, USA.METHODS：A total of 40 Wistar rats were equally and randomly divided into MODS group and control group. Suspension of E. coil strain O127 H6 containing BaSO4 and saline were sterilely injected into the abdominal cavity of rats in the MODS and control groups, respectively.MAIN OUTCOME MEASURES：Immunohistochemical double-staining and confocal laser scanning microscopy were used to observe the morphological changes in intestinal cholinergic nerves and ICC in the deep muscular plexus network. Electron microscopy was employed to evaluate the ultrastructural features of ICC in the deep muscular plexus of rats with MODS.RESULTS：Compared with the control group, the distributions and densities of cholinergic/nitrergic newes and ICC in the deep muscular plexus were significantly decreased in the MODS group （P 〈 0.01）. The enteric nerve-ICC network were disrupted.CONCLUSION：There is ultrastructural injury in the ICC in the deep muscular plexus and enteric nerves of the intestine in rats with MODS, which may be associated with the dysmotility of the gastrointestinal tract in MODS.

Morphological Changes in Network of Enteric Nerve-Interstitial Cells of Cajal-Smooth Muscle Cells in Rats with Multiple Organ Dysfunction Syndrome and Therapeutic Effects of Dachengqi Decoction (大承气汤)

Objective： To observe the effects of Dachengqi Decoction （大承气汤, DCQD） on morphological changes in the network of enteric nerve-interstitial cells of Cajal （ICCs）-smooth muscle cells （SMC） of enteric deep muscular plexuses （DMP） in the rats with multiple organ dysfunction syndrome （MODS）. Methods： One hundred Wistar rats of both sexes weighing 200 to 250 g were randomly divided into the control group, MODS group, and DCQD group. The morphologic changes of enteric nerve-ICC-SMC network in the DMP of intestine was observed using c-Kit and vesicular acetylcholine transporter/neuronal nitric oxide synthase immunohistochemical double-staining with whole-mount preparation technique, confocal laser scanning microscopy, and electron microscopy. Results： Compared with the control group, the distribution and densities of cholinergic/nitrergic nerves and ICC in the DMP （ICC-DMP） of intestine in the MODS group were significantly decreased （P0.01）, and the network of cholinergic nerve-ICC-SMC was disrupted; and the ultrastructural features of ICC-DMP, enteric nerve, and SMC were severely damaged. After treatment with DCQD, the damage in the network of enteric nerve-ICC-SMC was significantly recovered. Compared with the MODS group, the distribution and densities of cholinergic/nitrergic nerves and ICC-DMP in the DCQD group were significantly increased （P0.01）; and the ultrastructural features of ICC-DMP, enteric nerve, smooth muscle cells were significantly recovered. Conclusions： DCQD can improve the gastrointestinal motility in MODS. The mechanism may be related to the effect of repairing the damages in the network of enteric nerve-ICC-SMC.