硫化氢对大鼠肠缺血再灌注后回肠收缩活性的保护作用

Protective Effect of Hydrogen Sulfide on Contractile Activity of Rat Ileum Induced by Ischemia-reperfusion

背景:肠缺血再灌注(I/R)在临床中较为常见,并可引起严重的并发症,目前仍缺乏有效的治疗药物。目的:研究硫化氢(H2S)对大鼠肠I/R后离体回肠收缩活性的影响及其机制。方法:24只Sprague-Dawley大鼠随机分为正常组、假手术组、I/R组(I1 h/R4 h)、H2S组(再灌注前20 min腹腔内注射硫氢化钠10μmol/kg)。记录离体回肠自发收缩频率和曲线下面积(AUC),观察离体回肠对KCl(30 mmol/L)、乙酰胆碱(Ach)(10-5mol/L)、电场刺激(EFS)(30 V,10 Hz,1.00 ms,10 s)的反应。以免疫荧光染色检测肠肌间神经丛中Hu、胆碱乙酰转移酶(ChAT)阳性神经元表达。结果:与假手术组相比,I/R组和H2S组大鼠离体回肠自发收缩频率、对KCl和Ach的反应无明显改变。I/R组自发收缩AUC和对EFS的反应明显下降(P<0.05),Hu、ChAT阳性神经元表达均明显降低(P<0.05);给予H2S干预后,上述指标均明显升高(P<0.05)。结论:H2S对大鼠肠I/R后回肠收缩活性可产生保护作用,其机制可能是减轻了肠神经元尤其是兴奋性神经元的损伤。

Background： Ischemia-reperfusion（I/R） injury is common and can cause severe complications,but there are only a few drugs showing promising effects.Aims： To investigate the protective effect and mechanism of hydrogen sulfide（H2S） on the contractile activity of isolated ileum induced by I/R in rats.Methods： Twenty-four Sprague-Dawley rats were randomly divided into normal control group,sham-operated group,I/R（I1 h/R4 h） group,H2S group（NaHS 10 μmol/kg injected intraperitoneally 20 minutes before reperfusion）.Functional studies were carried out by recording the frequency and area under curve（AUC） of spontaneous contraction of isolated ileum,and responses to KCl（30 mmol/L）,acetylcholine（Ach）（10-5 mol/L） and electrical field stimulation（EFS）（30 V,10 Hz,1.00 ms,10 s）.Immunofluorescence staining was used to detect the expressions of Hu-positive and choline acetyl transferase（ChAT）-positive enteric neurons in myenteric plexus.Results： Compared with sham-operated group,no significant differences in frequency of spontaneous contraction,responses to KCl and Ach were found in I/R group and H2S group.AUC of spontaneous contraction and the response to EFS,and expressions of Hu-positive and ChAT-positive enteric neurons were significantly decreased（P0.05）.After intervention with H2S,all the above-mentioned indices significantly increased（P0.05）.Conclusions： H2S shows protective effect on contractile activity of rat ileum induced by I/R.The mechanism is probably related to the alleviation of enteric neurons injury by H2S,especially the excitatory neurons.