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Objective To evaluate the effect of dexmedetomidine pretreatment on Toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) signaling pathway during intestinal ischemia-reperfusion (I/R) in rats.Methods Twenty-four male Spragne-Dawley rats,weighing 180-220 g,were divided into 3 groups (n =8 each) using a random number table method:sham operation group (S group),intestinal I/R group (I group) and dexmedetomidine pretreatment group (DP group).Intestinal I/R model was established by occlusion of the superior mesenteric artery for 1 h followed by 2-h reperfusion in anesthetized rats.Dexmedetomidine 100 μg/kg was intraperitoneally injected at 30 min before ischemia in DP group.Blood samples were collected from hearts at the end of reperfusion for determination of the serum intestinal fatty acid binding protein (I-FABP) level by enzyme-linked immunosorbent assay.The intestinal tissues were obtained at the end of reperfusion for examination of pathologic changes and for determination of tumor necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1β) contents (by enzyme-linked immunosorbent assay) and expression of TLR4,MyD88,phosphorylated NF-κB p65 (p-NF-κB p65) in total protein and NF-κB p65 in nucleoprotein (by Western blot).The degree of intestinal tissue damage was graded using Chiu's scoring system.Results Compared with S group,the Chiu's score and concentrations of IFABP in serum and contents of TNF-α and IL-1β in intestinal tissues were significantly increased,and the expression of TLR4,MyD88 and p-NF-κB p65 in total protein and NF-κB p65 in nucleoprotein was up-regulated in I/R group,and the Chiu's score was significantly increased,the expression of MyD88 and p-NF-κB p65 was up-regulated (P＜0.05),and no significant change was found in serum I-FABP concentration,contents of TNF-α and IL-1β,or expression of TLR4 in total protein and NF-κB p65 in nucleoprotein in DP group (P＞0.05).Compared with I/R group,the Chiu's score,serum I-FABP concentration,and contents of TNF-α and IL-1β were significantly decreased,and the expression of TLR4,MyD88 and p-NF-κB p65 in total protein and NF-κB p65 in nucleoprotein was down-regulated in DP group (P＜0.05).Conclusion The mechanism by which dexmedetomidine pretreatement mitigates intestinal I/R injury may be related to inhibiting activation of TLR4/NF-κB signaling pathway in rats.
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Objective To observe the effects of the preconditioning of ulinastatin on GES-1 cell injury induced by oxygen and glucose deprivation (OGD). Methods GES-1 cells were cultured in vitro and divided into three groups: normal control group (group N), oxygen and glucose deprivation group (group O), and ulinastatin preconditioning group (group U). The OGD model of GES-1 cells were established by glucose-free medium and three-gas incubator for 6h. Ulinastatin was added to group U 12h before the deprivation of oxygen and glucose. The cell viability and apoptosis were determined by cck-8 and flow cytometry respectively. Western Blot was used to examine the protein expression of Caspase-3 and Cleaved Caspase-3. The TRPV1 mRNA expression was measured by quantitative real-time PCR. Results As compared with group N, the viability of GES-1 was decreased, the apoptotic rate and the expression of Caspase-3 and Cleaved Caspase-3 were increased, and the TRPV1 mRNA expression decreased greatly in group O (P < 0.05). As compared with group O, the aforementioned changes were significantly inhibited in group U. Conclusions Ulinastatin preconditioning could effectively inhibit GES-1 cell injury induced by OGD, which may be related to the inhibition of apoptosis and the upregulation of TRPV1 mRNA expression.
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Objective To study the effect of APETx2 on the expression of ASIC3 APETx2 in a rat model of acute gastric mucosal lesion(AGML). Methods Twenty-four Wistar rats were randomly assigned to three groups in equal number : normal control group, water immersion restraint stress (WIRS) group, APETx2 treatment group. AGML was induced by WIRS for 6 hours, and APETx2 (25 μg/kg) was injected intraperitoneally before the onset of stress. Intragastric pH and gastric histopathological changes were measured and the expression of ASIC3 mRNA in DRG neurons projecting to rat stomach was examined by real-time PCR. Immunohistochemistry was performed to detect the localization of ASIC3. Results Compared with the normal control group, the WIRS group showed obvious gastric injury with lower values of intragastric pH and extensive expression of ASIC3 in the DRG neurons (P < 0.05). The treatment with APETx2 before the onset of WIRS significantly alleviated the gastric mucosal injury, decreased gastric acidity and reduced ASIC3 expression in DRG neurons (P < 0.05). Conclusions ASIC3 expression in DRG neurons projecting to rat stomach is strongly associated with gastric mucosal lesion and acidosis in the WIRS model. APETx2 can improve gastric acidosis and prevent the occurrence of these lesions.
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Objective To observe the protective effect of sufentanil pretreatment on the rats with acute gastric mucosa lesion (AGML) induced by water immersion and restrain stress (WIRS) and its effect on TRPV1 mRNA expression in the hypothalamus and gastric mucosa. Methods Thirty male Wistar rats were randomly designed into 3 groups, including the normal control group (Group NC, n = 10), the group treated with WRIS for 6 h (Group WIRS, n = 10) and the group pretreated with sufentanil (Group SF, n = 10). The model of AGML was established by the classic WIRS method , and observed for the general extent of gastric mucosal injury at WIRS for 6 hr, and calculated gastric mucosal injury ulcer index (UI) and the PH value of gastric juice; The quantification of TRPV1 mRNA expression in hypothalamus and gastric mucosa was performed using quantitative real-time PCR; In addition, the activity of super oxide dismutase (SOD) and the level of malondialdehyde (MDA) in serum were detected. Results Compared with group NC, gastric mucosal in Group WIRS was injured more seriously , and the UI and the activity of MDA were also obviously increased , but the change of SOD activity was not apparent; The TRPV1 expression in gastric mucosal decreased apparently. Sufentanil pretreatment could effectively relieve gastric mucosal injury induced by WIRS , and make the UI and the activity of MDA decreased , and up-regulate TRPV1 mRNA expression in the hypothalamus and gastric mucosa. Conclusions Sufentanil pretreatment can effectively relieve AGML induced by WIRS , which may be related to the control of oxidative stress response , the reduced gastric acid secretion , and the upregulation of the TRPV1 mRNA expression in the central and periphera nerve.
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AIM: To observe the influence of the selective decontamination of the digestive tract (SDD) and caecosomy/colonic irrigation on gut endotoxin/bacteria translocation following acute severe pancreatitis (ASP). METHODS: Twenty three pigs weighing 16-22 kg were divided into four groups. Group I (n=5): sham-control; Group Ⅱ (n=6): ASP-control; Group Ⅲ (n=6): gntamicin [(8.55?10~5?5.70?10~4) units/time] and nystatin [(1.37?10~5?9.00?10~3) units/time] were fed orally every 8 h for 1 week before the induction of ASP; Group Ⅳ (n=6): caecostomy was performed before the induction of ASP. ASP was induced by infecting 1 mL/kg BW of combined solution of 5% sodium taurocholate and (8-10)?10~6 BAEE units/L of trypsin into pancreas via pancreatic duct. Systemic plasma endotoxin levels were quantified by the chromogenic limulus amebocyte lysate (LAL) technique. Specimens of tissue from mesenteriolum and mesocolon lymph nodes, lung, lymph nodes in hilus pulmonis, pancreas and the samples of both portal and systemic blood were collected before and at 72 h following ASP and cultured for aerobic as well as anaerobic bacteria growth. Positive specimens were subcultured and the bacteria identified by standard procedure. RESULTS: Preventive SDD not only effectively reduced the amount of bacteria in stool (P