Colon mucosal injury caused by water jet malfunction during a screening colonoscopy:A case report

BACKGROUND Screening colonoscopies are routinely performed and have low occurrences of adverse events such as perforation,bleeding,infection,and post-polypectomy syndrome.True device related adverse events are rarely reported in the literature.CASE SUMMARY We report a case of a 51-year-old patient without past medical history who presented for her first screening colonoscopy.The patient was thought to have friable mucosa in the cecum and oozed upon water irrigation during screening colonoscopy.It was later identified that the colonoscope used during the index procedure had malfunctioned and produced a pin-point water jet which damaged the colon mucosa of cecum.The maintenance service identified a piece of rubber fragment lodged in the instrument component at the tip of the scope,resulting in high pressure water jet.Repeat colonoscopy with a functioning colonoscope confirmed normal colon mucosa without friability.CONCLUSION This is the first report of mucosa injury from a colonoscope water jet malfunction.Endoscopists should recognize the potential for endoscopic malfunction.

Mast Cells in Adjacent Normal Colon Mucosa rather than Those in Invasive Margin are Related to Progression of Colon Cancer

Objective: Mast cells (MC) reside in the mucosa of the digestive tract as the first line against bacteria and toxins. Clinical evidence has implied that the infiltration of mast cells in colorectal cancers is related to malignant phenotypes and a poor prognosis. This study compared the role of mast cells in adjacent normal colon mucosa and in the invasive margin during the progression of colon cancer. Methods: Specimens were obtained from 39 patients with colon adenomas and 155 patients with colon cancers treated at the Sun Yat-sen University Cancer Center between January 1999 and July 2004. The density of mast cells was scored by an immunohistochemical assay. The pattern of mast cell distribution and its relationship with clinicopathologic parameters and 5-year survival were analyzed. Results: The majority of mast cells were located in the adjacent normal colon mucosa, followed by the invasive margin and least in the cancer stroma. Mast cell count in adjacent normal colon mucosa (MCCadjacent) was associated with pathologic classification, distant metastases and hepatic metastases, although it was not a prognostic factor. In contrast, mast cell count in the invasive margin (MCCinvasive) was associated with neither the clinicopathlogic parameters nor overall survival. Conclusion: Mast cells in the adjacent normal colon mucosa were related to the progression of colon cancer, suggesting that mast cells might modulate tumor progression via a long-distance mechanism.

MicroRNA exhibit altered expression in the inflamed colonic mucosa of ulcerative colitis patients

To investigate the miRNA expression in colonic mucosal biopsies from endoscopically inflamed and non inflamed regions of ulcerative colitis (UC) patients. METHODSColonic mucosal pinch biopsies were analyzed from the inflamed and non inflamed regions of same UC patient. Total RNA was isolated and differential miRNA profiling was done using microarray platform. Quantitative Real Time PCR was performed in colonic biopsies from inflamed (n = 8) and non-inflamed (n = 8) regions of UC and controls (n = 8) to validate the differential expression of miRNA. Potential targets of dysregulated miRNA were identified by using in silico prediction tools and probable role of these miRNA in inflammatory pathways were predicted. RESULTSThe miRNA profile of inflamed colonic mucosa differs significantly from the non-inflamed. Real time PCR analysis showed that some of the miRNA were differentially expressed in the inflamed mucosa as compared to non inflamed mucosa and controls (miR-125b, miR-223, miR-138, and miR-155), while (miR-200a) did not show any significant changes. In contrast to microarray, where miR-378d showed downregulation in the inflamed mucosa, qRT-PCR showed a significant upregulation in the inflamed mucosa as compared to the non inflamed. The in silico prediction analysis revealed that the genes targeted by these miRNAs play role in the major signaling pathways like MAPK pathway, NF-κB signaling pathway, cell adhesion molecules which are all assciated with UC. CONCLUSIONThe present study reports disease specific alteration in the expression of miR-125b, miR-155, miR-223 and miR-138 in UC patients and also predict their biological significance.

Qualitative and quantitative analyses of the bifidobacterial microbiota in the colonic mucosa of patients with colorectal cancer, diverticulitis and inflammatory bowel disease

AIM： To characterize the bifidobacterial microbiota of the colonic mucosa in patients with colon cancer, inflammatory bowel disease or diverticulitis. METHODS： A sample of the distal colonic mucosa was taken during surgery from a total of 34 patients, twenty-one with diagnosed colorectal cancer, nine with diverticulitis and four with inflammatory bowel disease, requiring surgery for their condition. Bacterial DNA was extracted from the resected mucosal samples and bifidobacterial mucosa-associated microbiota was qualitatively and quantitatively determined by means of qualitative and quantitative PCR. RESULTS： Bifidobacteria were found in 100% of the samples from patients with diverticulitis or IBD and a 76% of those suffering colon cancer. The species B. Iongum and B. bifidum were the most widely found, followed by B. animalis, B. catenulatum and B. adolescentis. B. breve, B. dentium and B. angulatum were not detected in any sample. A significantly higher occurrence of B. Iongum was observed in patients with diverticulitis than in those with colon cancer or IBD （100%, 62% and 75%, respectively, P 〈 0.05）. Similar results were obtained for B, animalis （56%, 0% and 25%, P 〈 0.05）, while B. adolescentis was only found in the mucosa from patients with colon cancer （5 out of 21, 24%）. At the quantitative level, patients with colon cancer or IBD showed lower counts of total Bifidobacterium （4.94 and 5.91 vs 6.96 log Cells/sample, respectively, P 〈 0.05） and of the species B. longum （4.05 and 4.79 vs 6.76, P 〈 0.05） than those with diverticulitis.CONCLUSION： Aberrancies in mucosa associated microbiota are present in different intestinal diseases. This may indicate a role of the microbiota in the pathogenesis of these diseases.

Effects of moxibustion on heat-shock protein 70 expression in the spinal cord and colonic mucosa in a rat model of ulcerative colitis

Pathological changes in the colon are closely associated with the spinal cord, and innervation of spinal cord can regulate cellular functions. Our previous studies verified that moxibustion protects and restores the colonic mucosa, but the mechanisms of action remain unknown. The present study observed the effects of moxibustion and salicylazosulfapyridine on expression of heat-shock protein 70 （HSP70） and its mRNA in the spinal cord and colonic mucosa of ulcerative colitis rats. Results demonstrated that moxibustion and salicylazosulfapyridine increased HSP70 mRNA expression in the spinal cord and colonic mucosa of ulcerative colitis rats. The decreased transcriptional activity of HSP70 in the spinal cord and colonic mucosa might participate in damage to the colonic mucosa in ulcerative colitis rats. Moxibustion exerted protective effects on colonic mucosa by up-regulating HSP70 transcriptional activity in the spinal cord and colonic mucosa.

Effect of tight junction protein of intestinal epithelium and permeability of colonic mucosa in pathogenesis of injured colonic barrier during chronic recovery stage of rats with inflammatory bowel disease

Objective: To discuss the changes in the tight junction protein of intestinal epithelium and permeability of colonic mucosa and its possible mechanism by building the rat mode of inflammatory bowel disease at the chronic recovery stage. Methods: A total of 36 SD rats were divided into the model group and control one according to the random number table, with 18 rats in each group. Rats in the model group were given the 3% dextran sulfate sodium solution by the way of drinking for 7 d to build the rat model of inflammatory bowel disease, while rats in the control group were given free drinking of water. Six rats were executed at day 7, 14 and 21 respectively. The colonic tissues were collected from rats to observe the pathological changes of colonic mucosa. The activity of myeloperoxidase was detected and the white blood count was performed for rats in each group. The Ussing chamber technique was employed to detect the transepithelial electrical resistance(TER) and short-circuit current(SC) of colonic mucosa of rats in different time intervals; the quantum dots labeling technique was employed to detect the expression level of claudin-1 and claudin-2 in the colonic tissues. Results: After the successful modeling, the weight of rats in the model group was significantly reduced, while the disease activity index score was increased. The weight was at the lowest level at day 14 and then it began to increase afterwards. The disease activity index score was at the highest level at day 12 and then it began to decrease gradually. The activity of myeloperoxidase and WBC for rats in the model group all reached the peak value at day 14 and then decreased gradually. There was no significant difference in the changes of TER and SC in different time intervals for rats in the control group(P>0.05). TER of model group was at the lowest level at day 14 and then increased gradually; SC was at the highest level at day 14 and then decreased gradually. TER of model group at day 7, 14 and 21 was significantly lower than that of control group, while SC of model group was significantly higher than that of control group(P<0.05). There was no significant difference in the change of mean fluorescence intensity of claudin-1 and claudin-2 in different time intervals for rats in the control group(P>0.05). The claudin-1 and claudin-2 for rats in the model group reached the highest level at day 14 and then decreased gradually. The claudin-1 and claudin-2 of model group at day 7, 14 and 21 was significantly higher than that of control group(P<0.05). Conclusions: After the acute stage, the inflammatory bowel disease is then in the chronic recovery stage; the increased permeability of colonic mucosa and increased expression of tight junction protein of intestinal epithelium are closely related to the pathogenesis and development of disease. The tight junction protein plays a key role in the pathogenesis of injured colonic barrier of inflammatory bowel disease.

Corticotropin-releasing factor receptor subtype 2 in human colonic mucosa: Down-regulation in ulcerative colitis

AIM: To assess corticotropin-releasing factor receptor 2 (CRF 2 ) expression in the colon of healthy subjects and patients with ulcerative colitis (UC). METHODS: We examined CRF2 gene and protein expression in the distal/sigmoid colonic mucosal biopsies from healthy subjects and patients with UC (active or disease in remission), human immunodeficiency virus (HIV) and functional bowel disease (FBD) by reverse transcriptionpolymerase chain reaction and immunofluorescence. RESULTS: Gene expression of CRF2 was demonstrated in the normal human colonic biopsies, but not in the human colorectal adenocarcinoma cell line Caco2. Receptor protein localization showed immunoreactive CRF 2 receptors in the lamina propria and in the epithelial cells of the distal/sigmoid biopsy samples. Interestingly, CRF 2 immunoreactivity was no longer observed in epithelial cells of patients with mild-moderately active UC and disease in remission, while receptor protein expression did not change in the lamina propria. No differences in CRF 2 expression profile were observed in distal/sigmoid intestinal biopsies from HIV infection and FBD patients, showing no signs of inflammation. CONCLUSION: The down-regulation of the CRF2 receptor in the distal/sigmoid biopsies of UC patients is indicative of change in CRF 2 signalling associated with the process of inflammation.

Proteomic analysis of down-regulated proteins in colonic mucosa of chronic slow transit constipation rats

Objective： To investigate the alternations of proteins in the colonic mucosa of chronic slow transit constipation （STC） rats with a 2-DE-based proteomic method and analyze the function of these down-regulated proteins so as to provide theoretical basis for the pathogenesis of intestinal mucosa of chronic STC rats. Methods： STC model was established by feeding rats with 8 mg/（kg＇d） diphenoxylate for 120 d. An experimental model of chronic STC rat was used for separation of proteomics from colonic mucosa using two-dimensional electrophoresis （2-DE）. Proteins altered in expressional level were identified by Image Master 2DElite, mass spectrometry, and bibliometrics were applied to identify the differential protein expression and their clinical s observed in the pathogenesis lgn of ificance and function were analyzed. Results： Obvious differential protein expression was STC, including mast cell protease （A1）, non-specific dipeptidase （A2） and chondrosome succinate dehydrogenase precursor （A3）. The expressions of A1, A2 and A3 were down-regulated in the gel graph of STC rats Conclusion： The down-regulation of chondrosome succinate dehydrogenase, mast cell protease as well as non-specific dipeptidase in rat colon suggests the functional impairment of the oxidoreduction of mitochondrion is very important in the genesis and development of STC. The immunological reaction of STC rats is weakened, and the function of digesting and absorbing protein may be damaged to some extent.

DISTINGUISHING BETWEEN HYPERPLASTIC AND ADENOMATOUS POLYPS AND NORMAL COLONIC MUCOSA BY USING MULTIPHOTON LASER SCANNING MICROSCOPY

Precisely distinguishing between hyperplastic and adenomatous polyps and normal human colonic mucosa at the cellular level is of great medical significance.In this work,multiphoton laserscarming microscopy(MPLSM)was used to obtain the high.-contrast images and the morpho-logical characteristics from normal colonic mucosa,hyperplastic polyps and tubular adenoma.Byintegrating the length and area measurement tools and computing tool,we quantified thedifference of crypt morphology and the alteration of nuclei in normal and diseased human colonicmucosa.Our results demonstrated that the morphology of crypts had an obvious tendency tocystic dilatation or elongated in hyperplastic polyps and tubular adenoma.The cont ent andnumber of mucin droplets of the scattered goblet cells had a piecemeal reduction in hyperplastic polyps and a large decrease in tubular adenoma The nuclei of epithelial cells might be elongated and pseudostratified,but overt dysplasia was absent in hyperplastic polyps.Nevertheless,thenuclei showed enlarged,crowded,stratified and a rod-like structure,with loss of polarity intubular adenoma.These results suggest that MPLSM has the capacity to distinguish betweenhyperplastic and adenomat ous polyps and normal human colonic mucosa at the celular level.

Identification of differentially expressed genes in normal mucosa,adenoma and adenocarcinoma of colon by SSH

AIM: To construct subtracted cDNA libraries and further identify differentially expressed genes that are related to the development of colorectal carcinoma(CRC). METHODS: Suppression subtractive hybridization(SSH) was done on cDNAs of normal mucosa, adenoma and adenocarcinoma tissues from the same patient. Three subtracted cDNA libraries were constructed and then hybridized with forward and backward subtracted probes for differential screening. Positive clones from each subtracted cDNA library were selected for sequencing and BLAST analysis. Finally, virtual Northern Blot confirmed such differential expression. RESULTS: By this way, there were about 3-4 X 10(2) clones identified in each subtracted cDNA library, in which about 85% positive clones were differentially screened. Sequencing and BLAST homology search revealed some clones containing sequences of known gene fragments and several possibly novel genes showing few or no sequence homologies with any known sequences in the database. CONCLUSION: All results confirmed the effectiveness and sensitivity of SSH. The differentially expressed genes during the development of CRC can be used to shed light on the pathogenesis of CRC and be useful genetic markers for early diagnosis and therapy.

Regulating effect of Tong Xie-Yao Fang on colonic epithelial secretion via Cl- and HCO3- channel

AIM To investigate the pharmacological effect of Tong XieYao Fang(TXYF) formula, a Chinese herbal formula, on Diarrhea-predominant irritable bowel syndrome(D-IBS) rats.METHODS In a neonatal maternal separation plus restraint stress(NMS + RS) model of D-IBS, male Sprague Dawley rats were randomly divided into two groups(NMS + RS group and TXYF-formula group) with no handlings were used as controls(NH group). Starting from postnatalday 60, rats in TXYF-formula group were administered TXYF-formula(4.92 g/100 g bodyweight) orally twice a day for 14 consecutive days while NH group and NMS + RS group were given distilled water. Using short-circuit current technology, we observed 5-HT-induced changes of current across ion channels, such as cystic fibrosis transmembrane conductance regulator(CFTR) Clchannel, epithelial Na+ channel(ENaC), Ca2+-dependent Cl- channel(CACC), Na+-K+-2Cl- co-transporter(NKCC), and Na+-HCO-3 co-transporter(NBC), in the colonic epithelium of three groups after exposure to drugs and specific blockers with a Power Lab System(AD Instruments International).RESULTS Under basal conditions, the changes of short-circuit current(?Isc, μA/cm2) induced by 5-HT were similar in NH group and TXYF-formula group, and both higher than NMS + RS group(70.86 μA/cm2 ± 12.32 μA/cm2, 67.67 μA/cm2 ± 11.68 μA/cm2 vs 38.8 μA/cm2 ± 7.25 μA/cm2, P < 0.01, respectively). When CACC was blocked by 4,4′-diisothiocyanato-stilbene-2,2′-disulfonic acid, 5-HT-induced ?Isc was smaller in NMS + RS group than in NH group and TXYF-formula group, respectively(48.41 μA/cm2 ± 13.15 μA/cm2 vs 74.62 μA/cm2 ± 10.73 μA/cm2, 69.22 μA/cm2 ± 11.7 μA/cm2, P < 0.05, respectively). The similar result could be obtained when ENaC was blocked by Amiloride(44.69 μA/cm2 ± 12.58 μA/cm2 vs 62.05 μA/cm2 ± 11.26 μA/cm2, 62.11 μA/cm2 ± 12.01 μA/cm2, P < 0.05, respectively). However, when CFTR Cl- channel was blocked by 1,1-dimethyl piperidinium chloride(DPC), 5-HT-induced ?Isc did not significantly differ in three groups(42.28 μA/cm2 ± 10.61 μA/cm2 vs 51.48 μA/cm2 ± 6.56 μA/cm2 vs 47.75 μA/cm2 ± 7.99 μA/cm2, P > 0.05, respectively). The similar results could also be obtained in three groups when NBC and NKCC were respectively blocked by their blockers.CONCLUSION TXYF-formula can regulate the Cl- and HCO-3 secretion of colonic mucosa via CFTR Cl- channel, Cl-/HCO-3 exchanger, NBC and NKCC co-transporters.

Simultaneous occurrence of colonic adenocarcinoma and MALT lymphoma:A series of three cases

Simultaneous development of adenocarcinoma and primary B cell lymphoma of mucosa-associated lymphoid tissue(MALT) lymphoma of the colon is rare;only one case has so far been reported out of 13 cases with the coexistence of colonic adenocarcinoma with involvement of the colon by lymphoma.We hereby present three more cases,two females(aged 75 and 71 years) and a male(aged 72 years).All three underwent colectomy based on a preoperative biopsy revealing colonic carcinoma.Histological examination of the resection specimens disclosed a colonic adenocarcinoma in two cases,whereas a tubulovillous adenoma with superficial foci of intraepithelial adenocarcinoma was seen in the thirdcase.Moreover,in all three cases,a coexisting MALT lymphoma was diagnosed in the colon(1 case),in both colon and adjacent lymph nodes(1 case) or in colonic lymph nodes and omentum(1 case).In the last case,a post-operative bone marrow biopsy revealed extensive infiltration of the bone marrow,due to which the patient received postoperative chemotherapy.Diagnostic and treatment issues are briefly discussed.

Comparison of the Colonization Ability of Autochthonous and Allochthonous Strains of Lactobacilli in the Human Gastrointestinal Tract

Bacteria of the genus Lactobacillus are widely used as oral probiotics due to their putative health benefits. In this study, we compared the colonization ability of two Lactobacillus strains that were identified as autochthonous to the human gastrointestinal tract (Lactobacillus reuteri ATCC PTA 6475 (MM4-1a) and (Lactobacillus mucosae FSL-04) with that of an allochthonous strain (Lactobacillus acidophilus DDS-1). Colonization ability was tested in a single-blinded, cross-over study, with twelve human subjects. The test strains were quantified in fecal samples by two independent methods, selective plating and molecular typing and quantitative real time PCR. The study revealed that the two autochthonous strains (L. reuteri ATCC PTA 6475 and L. mucosae FSL-04) reached higher population levels in fecal samples and were recovered more frequently from subjects compared to the allochthonous strain (L. acidophilus DDS-1). All three strains became undetectable 8 days after the end of consumption with one exception, showing that persistence of all three strains remains short term in most individuals. In conclusion, this study showed that autochthonous Lactobacillus strains can be established more efficiently, albeit temporarily, in the human gastrointestinal tract, suggesting that evolutionary and ecological characteristics could be valuable criteria for the selection of probiotic strains.

内镜下结肠黏膜切除术治疗结肠腺瘤的临床疗效分析

目的分析内镜下结肠黏膜切除术治疗结肠腺瘤的临床疗效。方法选取某院2020年3月~2023年3月纳入的80例结肠腺瘤患者,按照随机数字法分为对照组(n=40)和观察组(n=40),其中对照组采用常规内镜下电凝电切手术治疗,观察组采用内镜下结肠黏膜切除术治疗。评估两组患者手术相关指标、手术治疗结果、手术治疗情况。结果治疗后,观察组手术时间及平均住院天数明显短于对照组,且肿瘤完全切除,观察组手术切除率高于对照组(P<0.05);治疗后,两组患者的迟发性出血发生率经比较差异无统计学意义(P>0.05),观察组术后穿孔及术中出血明显少于对照组(P<0.05);治疗后,观察组术后残留率、残留复发率及术后复发率均低于对照组,术后并发症明显更少(P<0.05)。结论内镜下结肠黏膜切除术治疗可以有效缩短住院天数和手术时间,提高腺瘤完全切除率,且残留率较低,可以减少并发症的发生,具有较高的安全性。

白头翁汤对溃疡性结肠炎模型小鼠结肠黏膜及血清TNF-α、IL-6影响

目的:观察白头翁汤对溃疡性结肠炎(Ulcerative Colitis,UC)模型小鼠结肠黏膜及血清Tumor Necrosis Factor-α(TNF-α)、Interleukin 6(IL-6)的影响,探讨白头翁汤治疗UC的相关机制。方法:实验BALB/C小鼠60只,正常饲养7 d后,禁食不禁水24 h,然后随机分3组,即甲组(对照组)、乙组(造模组)、丙组(造模+中药组)。甲组正常饲养10 d,乙、丙两组采用三硝基苯磺酸联合乙醇药液灌肠法制备UC小鼠模型,其中乙组造模后正常饲养10 d,丙组造模后正常饲养并给予白头翁汤灌服共10 d,造模术后第10天,取血后处死各组小鼠,检测各组小鼠血清TNF-α、IL-6,剖开小鼠结肠,观察各组小鼠结肠黏膜并计分,进行统计学比较分析。结果:(1)乙组小鼠结肠黏膜出现明显的充血水肿、糜烂及溃疡形成,显微镜下可见上皮及腺体破坏、炎性细胞浸润、杯状细胞减少等,造模成功。(2)甲组与乙组相比,乙组结肠黏膜损伤程度较甲组明显加重(P<0.01),乙组血清TNF-α、IL-6明显高于甲组(P<0.01)。(3)甲组与丙组相比,丙组结肠黏膜损伤程度较甲组加重(P<0.01),丙组血清TNF-α明显高于甲组(P<0.01),丙组与甲组血清IL-6差异不明显(P>0.05)。(4)乙组与丙组相比,丙组结肠黏膜损伤程度较乙组明显减轻(P<0.01),丙组血清TNF-α、IL-6明显低于乙组(P<0.01)。结论:1UC模型小鼠存在某些免疫功能紊乱。2白头翁汤可减轻UC模型小鼠结肠黏膜的损伤及相关免疫功能的紊乱。3白头翁汤对UC病情的治疗可能是通过调节机体免疫紊乱达到的。

顽固性便秘病人结肠黏膜菌群的变化特征

目的:阐释顽固性便秘病人结肠黏膜菌群的变化特征。方法:本研究分为顽固性便秘组(n=10)和对照组(n=6)。通过结肠镜活检获取乙状结肠黏膜标本,提取DNA,PCR扩增后行变性梯度凝胶电泳,应用分子生物学分析软件对菌群结构的相似性、主成分和多样性进行分析。结果:顽固性便秘病人结肠黏膜菌群有明显改变,与对照组比,顽固性便秘病人结肠黏膜菌群物种丰富度和香农多样性指数均显著降低(P<0.01)。结论:顽固性便秘病人结肠黏膜菌群紊乱,表现为结肠黏膜菌群多样性减少。

复杂性尿道狭窄及并发症诊治的实验研究与临床运用

复杂性尿道狭窄或闭锁的处理一直是泌尿外科最棘手的难题之一,尤其是对初次或再次治疗失败后的复杂性超长段尿道狭窄或闭锁(>14 cm)患者的治疗,作者在治疗复杂性尿道狭窄及其并发症中取得了一系列的原创性成果。与国内外的同类研究比较,主要有以下发现和创新点。①在国际上首次提出并证实结肠黏膜可作为尿道替代物;临床治疗55例超长段尿道狭窄(平均15.2 cm)的结果提示结肠黏膜具有材源丰富、易于剥离、抗感染力强、皱缩率低等优点,适于14 cm以上尿道的重建,尤其是多次治疗失败的复杂性超长段尿道狭窄。②在国际上首次建立新型分期手术治疗复杂性超长段狭窄或闭锁,临床应用11例,疗效显著,为难治性前后尿道间长段狭窄或闭锁提供了一个新的思路。③在国际上首次阐述舌黏膜尿道重建的病理学特征及转归,建立大面积舌黏膜取材新技术;在国内率先开展舌黏膜尿道成形术,样本量为国内外最大。④在国际上首次建立了尿道压客观量化指标(90 cmH2O或较基础压提高40～50 cmH2O),用于评估球部尿道悬吊术中尿道压力。从而提高了手术成功率,减少了并发症,取得了显著治疗效果。该系列研究成果先后获省部科技进步一等奖和多项二等奖。

五苓散对腹泻模型大鼠结肠AQP4及AQP4mRNA表达的影响

目的:观察五苓散对腹泻模型大鼠结肠AQP4及AQP4mRNA表达的作用,揭示五苓散止泻作用的机理。方法:将SD大鼠随机分为正常对照组、腹泻模型组、氢氯噻嗪组、口服盐液组、五苓散低、中、高剂量组7组,观察大鼠腹泻状态并测体重等。分别于第4天上午、第7天上午取大鼠结肠,免疫组化法检测AQP4蛋白的表达,原位杂交方法检测AQP4 mRNA的表达。结果:腹泻模型组、口服盐液组、五苓散低剂量组结肠AQP4及AQP4mRNA表达明显下调,氢氯噻嗪组、五苓散中剂量组AQP4及AQP4mRNA表达下调但明显高于模型组,五苓散高剂量组结肠AQP4及AQP4mRNA表达下调不明显。结论:AQP4及AQP4mRNA表达下调是番泻叶致大鼠腹泻的机制之一,上调腹泻模型大鼠结肠AQP4及AQP4mRNA表达是五苓散的止泻机理之一,但与剂量相关,5.4g/kg灌胃效果较好。