酸敏感离子通道3在胃食管反流大鼠中的表达和意义

Expression and significance of acid-sensing ion channel 3 in rats with gastroesophageal reflux disease

目的检测酸敏感离子通道3(ASIC3)在胃食管反流大鼠食管黏膜及背根神经节(DRG)中的表达变化,探讨其在胃食管反流病(GERD)发病中的作用。方法将Sprague-Dawley雄性大鼠随机分为实验组(G组)和对照组(S组)。实验组采用限制幽门及结扎胃底方法建立GERD大鼠模型。于造模后15 d处死两组大鼠,通过HE染色对大鼠食管黏膜进行组织病理学检测,通过蛋白质印迹法(Western blotting)和实时定量聚合酶链反应(RT-PCR)检测大鼠食管黏膜及DRG中ASIC3蛋白及mRNA表达变化。结果HE染色显示G组大鼠食管黏膜慢性炎症改变,S组大鼠食管黏膜无异常;Western blotting显示G组大鼠DRG中ASIC3蛋白表达高于S组(6.75±0.74 vs 5.07±0.72)(P<0.05),食管黏膜中ASIC3蛋白表达高于S组(8.04±0.67 vs 7.31±0.740)(P<0.05);RT-PCR同样显示,G组大鼠DRG中ASIC3 mRNA表达高于S组(0.00030±0.00003 vs 0.00013±0.00002)(P<0.05),食管黏膜中ASIC3 mRNA表达高于S组(0.01073±0.00231 vs 0.00088±0.0007)(P<0.05)。结论 ASIC3在DRG及食管黏膜上表达上调可能是导致GERD食管内脏高敏感的原因之一。

Objective To determine the expression of acid-sensing ion channel 3 （ASIC3） in esophageal mucosa and dorsal root ganglion （DRG） in rats with gastroesophageal reflux disease （GERD）,and to explore its role in the pathogenesis of GERD.Methods Male Sprague-Dawley rats were randomly divided into two groups：experimental group （G group） and control group （S group）.The fundus of stomach of G group was ligated and the pylorus was restricted to establish GERD model.All the rats were sacrificed on day 15,the histopathology of sophgeal mucosa was observed,the expression of acid-sensing ion channel 3 （AIC3） protein and mRNA in esophagealmucosa and DRG were determined by Western blotting and real-time polymerase chain reaction （RT-PCR）.Results HE staining showed that chronic inflammatory changes were found in regions of esophgeal mucosa in G group where as normal in S group.Western blotting showed that the expression of ASIC3 protein in DRG was up-regulated in G group than that in S group （6.75 ±0.74 vs 5.07 ± 0.72） （P ＜ 0.05）,and the expression of ASIC3 protein of esophageal mucosa was increased in G group compared with S group （8.04 ±0.67 vs 7.31 ±0.740） （P ＜0.05） ; RT-PCR showed that the expression of ASIC3 mRNA of DRG was up-regulated in G group than that in S group （0.00030 ±0.00003 vs 0.00013 ±0.00002） （P ＜0.05）,the expression of ASIC3 mRNA of esophageal mucosa was increased in G group compared with S group （0.01073 ±0.00231 vs 0.00088 ± 0.0007） （P ＜ 0.05）.Conclusion The up-regulated expression of ASIC3 in DRG and esophgeal mucosa of rats with gastroesophageal reflux indicate that ASIC3 involved in the pathogenesis of esophageal visceral hypersensitivity.