急性心肌缺血对心脏神经节、心房、心室肌表达乙酰胆碱和孤啡肽的影响

Effects of Coronary Artery Occlusion on the Expressions of Acetylcholine and Nociceptin/Orphanin FQ in Cardiac Ganglia and Myocardium in Rats

目的：观察心脏神经节分布特征以及心脏神经节细胞，心房和心室肌表达乙酰胆碱（ACh）和孤啡肽（0FQ）的特性及结扎冠状动脉左前降支对其影响。方法：将大鼠随机分为对照组（sham组）和结扎冠状动脉组（CAO组）。于扎闭冠脉或者冠脉下穿线30min取心脏标本。采用HE．尼氏（Nissl）染色法、免疫荧光标记技术和酶联免疫吸附法（ELISA）检测分析神经节分布和ACh和OFQ的变化。结果：心脏神经节多见于心房脂肪垫内，大血管周围脂肪组织内、心房肌间．偶见于心室肌闻。神经节细胞呈强嗜碱性．被卫星细胞包绕，分别表达．共表达ACh和OFQ。CAO组ACh和OFQ共表达细胞数量增加13．5％．表达OFQ细胞增加4．3％．表达ACh细胞减少19．2％；神经节细胞．心房肌和心室肌OFQ荧光光密度分别增加22％、59％和27％（P〈0．01）；ACh荧光光密度分别降低28％、44％和36％（P〈0．01）。ELISA结果显示．结扎冠脉后30min，心房和左心室OFQ含量增加而ACh含量降低（P〈0．05）。结论：乙酰胆碱和孤啡肽表达于心脏神经节细胞和心房、心室肌．可能共同参与了急性心肌缺血早期病理过程。

Objective： The aim of the study was to investigate the expressions of acetylcholine （Ach） and Nociceptin/Orphanin FQ （OFQ） in cardiac ganglia and myocardium and the changes of compounds at early time of acute myocardial ischemia with a rodent experimental model. Method： Twenty-eight adult male Sprague-Dawley rats, weighing 250~300g, were randomly divided into sham operation group （Sham） and coronary artery occlusion group （CAO）, 14 rats in each group. The left anterior descending branch of coronary artery was occluded under anesthesia by ligation of the artery to establish the acute myocardial ischemia model. The animals in sham group experienced the same procedure, except ligation of the coronary artery. The heart was harvested at 30 minutes of CAO or the sham surgery.The consecutive transverse sections of the heart were made and assessed using HE and Nissl staining. The histological immunofluorescence assay and enzyme linked immunosorbent assay （ELISA） were performed to evaluate the changes of the expressions of the compounds in the heart. Result： The cardiac ganglia were located mainly in the fat pad around the large blood vessels and among the myocardium of the atria and the ventricles. The cardiac ganglion neurons were strongly basophilic and in polygonal or oval shapes, with a diameter of about 20 μm. The satellite cells were seen around the ganglion neurons. One hundred-ninety three ganglion cells in 15 ganglia of the rats in sham group and 240 cells in 15 ganglia of the CAO animals were evaluated. It was found CAO caused increases in the OFQ expressing cells, by 4.3%, Ach expressing cells, by 19.2% and the co-expression neurons of OFQ and Ach, by 13.5%. The analysis of the density of immunofiuorescence presented that CAO induced increases in the density of immunofiuorescence for OFQ, by 22%,59% and 27% （P 〈 0.01）, in the ganglion cells, atria and ventricles respectively, while the fluorescence for Ach was reduced in the CAO animals, by 28%, 44% and 36%, compared to the sham group. The results of ELISA also demonstrated a significant increase of OFQ and a reduction of Ach in atria and ventricles. Conclusion： Some of the cardiac ganglion neurons co-express Ach and OFQ. The expressions of Ach and OFQ were also observed in the myocardium of atria and the ventricles. Coronary artery occlusion caused reduction of Ach but up-regulation of OFQ in the ganglion cells and the myocardium of the hearts. The findings may indicate that the Ach and OFQ in the cardiac ganglia and myocardium participate in the pathology of acute myocardial ischemia.