中文摘要：

目的研究缺氧对肠上皮细胞丝切蛋白活化的影响及丝切蛋白活化与紧密连接蛋白带状闭合蛋白（ZO－1）分布变化的关系。方法建立人肠上皮细胞株Caeo－2单层细胞培养模型，取部分细胞按照随机数字表法分为对照组（不处理）、缺氧组（置于缺氧环境下）和常氧组（置于常氧环境下），取对照组细胞（样小数为9）及其他2组培养1、2、6、12、24h的细胞（各时相点样本数均为9）采用蛋白质印迹法检测丝切蛋白及磷酸化丝切蛋白的表达。另取细胞，按照随机数字表法分为缺氧组和对照组（处理同前），取对照组细胞和缺氧组缺氧1、2、6、12、24h的细胞采用激光扫描共聚焦显微镜观察纤维状肌动蛋白的形态与分布，荧光法检测纤维状肌动蛋白与球状肌动蛋白含量的比值，激光扫描共聚焦显微镜观察细胞形态及ZO－1的分布；该3个实验中对照组样本数依次为3、6、3，缺氧组各时相点样本数依次为3、6、3。对数据行重复测量方差分析、配对t检验、LSD-t检验。结果与对照组比较，常氧组细胞培养1～24h丝切蛋白发磷酸化丝切蛋白表达量均无明显变化（t值分别为－0．385～1．701、0．040～1．538，P值均大于0．05）。与对照组比较，缺氧纰细胞培养1～24h丝切蛋白表达量也无明显变化（t值为1．032～2．390，P值均大于0．05）；但磷酸化丝切蛋白表达量均明显降低（t值为4．563～22．678，P值均小于0．01），其中培养24h降至最低值。常氧组、缺氧组细胞各时相点丝切蛋白表达量相近（t值为－0．904～1．433，P值均大于0．05）；缺氧组细胞培养l、2、6、12、24h时磷酸化丝切蛋白表达量分别为0．87±0．08、0．78±0．05、0．89±0．07、0．68±0．07、0．57±0．06，均低于常氧绀（0．90±0．07、0．97±0．06、1．00±0．06、1．00±0．05、0．99±0．05，t值为3．193～16．434，P值均小?

英文摘要：

Objective To study the effect of hypoxia on cofilin activation in intestinal epithelial cells and its relation with distribution of tight junction protein zonula occecludens 1 （ ZO-1 ）. Methods The human intestinal epithelial cell line Caco-2 was used to reproduce monolayer eells. The monolayer-eeli speci- mens were divided into conlrol group （no treatment） , hypoxie group （exposed to hypoxia）, and nnrmnxic group （exposed Io normoxia） according to Ihe random number table. Western blotting wax used to detect the protein expressions of cofilin and phosphorylated eofilin （p-cofilin） of cells in normoxic group and hypoxic group exposed to normoxia or hypoxia for 1, 2, 6, 12, and 24 h and control group, with 9 samples in control group and 9 samples at each time point in the other two groups. The other monolayer-eell specimens were di- vided into hypoxic group （exposed to hypoxia） and control group （no treatment） according to the random number table. Cells in hypoxie group exposed to hypoxia for 1, 2, 6, 12, and 24 h and control group were obtained. Morphology and distribution of F-actin was observd with laser scanning confocal microscopy, the ratio of F-aetin to G-actin was determined by fluorescence method, and distribution of ZO-1 and cellular mor- phology were observed with laser scanning confoeal microscopy. The sample number of last 3 experiments was respectively 3, 6, and 3 in both hypoxic group （ at each time point） and control group. Data were pro- cessed with paired t test, analysis of variance of repeated measurement, and LSD-t test. Results The protein expressions of cofilin and p-cofilin of cells between normoxic group exposed to normoxia for 1 to 24 h and control group showed no significant changes （with t eofilin values from - 0. 385 to 1. 701, t p-cofilin values from 0. 040 to 1. 538, P values above 0.05 ）. There were no obvious differences in protein expressions of co- filin of cells between hypoxic group exposed to hypoxia for 1 to 24 h and control group （ with t