Porcine small intestinal epithelial cell from jejunum ( IPEC⁃J2) was used to study the regulation of porcine glucagon⁃like peptide⁃2 ( pGLP⁃2) on protein expressions of tight junction and its signaling pathway. Culture mediums were supplemented without ( control group) or with 10-9 mol/L pGLP⁃2 ( pGLP⁃2 group) , and 10-9 mol/L pGLP⁃2 and 10 μmol/L U0126 ( pGLP⁃2+U0126 group) , respectively. Each group had 3 replicates with 1 culture pore per replicate. Protein expressions of zonula occludens⁃1 ( ZO⁃1 ) , occluding, claudin⁃1 and extracellular regulated kinase 1/2 ( ERK1/2) in cytoplasm of IPEC⁃J2 were determined. The re⁃sults showed as follows: compared with control group, the supplementation of pGLP⁃2 in culture medium of IPEC⁃J2 significantly increased protein expressions of ZO⁃1, claudin⁃1, occludin, p42⁃ERK1/2 and p44⁃ERK1/2 ( P<0.05); compared with pGLP⁃2 group, the supplementation of U0126, an inhibitor of ERK1/2, in culture medium of IPEC⁃J2 significantly decreased protein expressions of the above proteins ( P<0.05) . The results suggest that ERK1/2 pathway is an important signaling pathway of pGLP⁃2 regulating tight junction pro⁃tein expressions in intestinal epithelial cells.%本试验以体外培养的仔猪空肠上皮细胞（ IPEC⁃J2）为研究对象，研究了猪胰高血糖素样肽－2（ pGLP⁃2）对紧密连接蛋白表达的调节及其信号传导机制。培养液中分别添加10－9 mol／L pGLP⁃2（ pGLP⁃2组）和10－9 mol／L pGLP⁃2、10μmol／L U0126（ pGLP⁃2＋U0126组），对照组不添加以上试剂，每组3个重复，每个重复1个培养孔。测定IPEC⁃J2胞质紧密黏连蛋白－1（ZO⁃1）、occludin、claudin⁃1以及细胞外信号调节激酶1／2（ERK1／2）蛋白表达量。结果表明：与对照组相比，IPEC⁃J2细胞培养液中添加pGLP⁃2显著增加了ZO⁃1、occludin、claudin⁃1以及p42⁃ERK1／2、p44⁃ERK1／2的蛋白表达量（P＜0．05）；与pGLP⁃2组相比，在IPEC⁃J2细胞培养液中加入 ERK1／2的抑制剂 U0126，显著降低了 ZO⁃1、occludin、claudin⁃1以及 p42⁃ERK1／2、p44⁃ERK1／2的蛋白表达量（ P＜0．05）。综合得出，ERK1／2通路是pGLP⁃2调控肠道上皮细胞紧密连接蛋白表达的一条重要信号通路。
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