胃电刺激对大鼠胃窦肌间神经丛Cajal间质细胞超微结构的影响

背景：前期研究发现胃窦肌间神经丛Caial间质细胞（ICC-MY）数量增多参与了长时程长脉冲胃电刺激（GES）对胃慢波的调控。目的：观察不同时程长脉冲GES对大鼠胃窦ICC-MY数量和超微结构的影响,进一步探讨GES调控胃慢波的可能机制。方法：建立Wistar大鼠GES模型。将模型大鼠分为3组,GES1组和GES2组选用适宜的刺激参数控制胃慢波,对照组不予GES。GES1组仅予刺激一次;GES2组每天刺激一次,连续20 d。完成GES后处死大鼠,取胃窦组织,行透射电子显微镜观察。结果：GES1组胃窦ICC-MY数量与对照组相比未见明显变化,GES2组ICC-MY数量较GES1组和对照组明显增多。GES1组和GES2组ICC胞质内线粒体和核糖体均较对照组增多。GES1组ICC突起与周围平滑肌细胞（SMC）直接相连,GES2组ICC与周围SMC紧密相连,对照组ICC与周围SMC之间未见明显连接。结论：胃窦ICC-MY数量和超微结构改变参与了长时程长脉冲GES对胃慢波的调控。

Effect of Gastric Electrical Stimulation on Ultrastructure of Interstitial Cells of Cajal in Antral Myenteric Nerve Plexus in Rats

Background:Previous study demonstrated that increase of interstitial cells of Cajal in antral myenteric nerve plexus (ICCs-MY) is involved in the modulatory effect of long-term,long pulse gastric electrical stimulation(GES) on gastric slow wave.Aims:To investigate the effect of long pulse GES with different time course on number and ultrastructure of antral ICCs-MY in rats for studying the possible mechanism of GES in modulating gastric slow wave.Methods:GES model was established in Wistar rats.The model rats were divided into three groups:GES1 group,GES2 group and control group. Optimal GES parameters were selected to entrain gastric slow wave in GES1 and GES2 groups.Rats in GES1 group were given GES once,and those in GES2 group were given GES daily for 20 days;rats in control group did not receive GES. Then all the rats were sacrificed,and the antral tissues were prepared and examined by transmission electron microscopy. Results:Number of antral ICCs-MY in GES2 group was significantly higher than that in GES1 group and control group, while no significant difference was seen between the latter two groups.Cytoplasmic mitochondria and ribosomes were more abundant in GES1 and GES2 groups than in control group.Direct connection between ICCs processes and surrounding smooth muscle cells(SMCs) could be visualized in GES1 group,tight connection was visualized between ICCs and SMCs in GES2 group,and no obvious connection was seen between ICCs and SMCs in control group.Conclusions:Changes of number and ultrastructure of antral ICCs-MY might be involved in the modulation of gastric slow wave by long-term,long pulse GES.