9-羧酸蒽对大鼠离体灌流心脏c-fos表达的影响

Effect of anthracene9carboxylic acid on cfos expression in isolated rat heart

目的：通过对氯通道抑制剂９－羧酸蒽（９－ＡＣ）诱导离体心肌ｃ－ｆｏｓ表达的观察，研究９－ＡＣ敏感性心肌细胞的分布，并与β－受体激动剂异丙肾上腺素（Ｉｓｏ）相比较．方法：采用离体心脏灌流技术和免疫组化ＡＢＣ法．结果：以２５μｍｏｌ／Ｌ的９－ＡＣ灌注９０ｍｉｎ后，与对照组相比，心肌组织内ＦＯＳ蛋白表达明显增加（Ｐ＜０．０１）．ＦＯＳ阳性细胞以左室外层、右室内层的心肌组织最多，其次是右室外层心肌，而左室内层阳性细胞极少，与对照组相似．中层心肌未见ＦＯＳ阳性细胞．Ｉｓｏ灌注组（０．５μｍｏｌ／Ｌ）的ＦＯＳ阳性细胞主要分布于左室外层及内层心肌组织内，而右室外层及内层较少．ＦＯＳ阳性细胞的数量多于９－ＡＣ组（Ｐ＜０．０１）．９－ＡＣ与Ｉｓｏ共同灌注后，ＦＯＳ阳性心肌细胞的数量与单独给药相比明显增多（Ｐ＜０．０１），但分布情况与Ｉｓｏ组相似．结论：９－ＡＣ可诱导大鼠心肌细胞表达ｃ－ｆｏｓ，其非均一性的分布提示９－ＡＣ敏感性磷酸酶在心肌细胞中具有区域特异性．与Ｉｓｏ的比较提示９－ＡＣ的作用可能是通过磷酸酶机制实现的．

AIM: cfos expression induced by anthracene9carboxylic acid (9AC, a Cl- channel blocker) in the isolated perfused rat heart was examined to study the distribution of 9ACsensitive myocytes. The effect of 9AC was further compared with that of isoproterenol (Iso). METHODS: Rat hearts were isolated and perfused with a modified Langendorff technique (nonrecirculating) for 90 min. The expression of FOS protein in the myocardium was examined by immunohistochemical staining. RESULTS: Inclusion of 9AC (25 mol/L)) in the perfusate caused a significant elevation in the number of FOSlike immunoreactive (FOSLI) cells in myocardium as compared with that of the control group (perfused with KH solution only). FOSLI cells were observed mainly in the outer layer of the left and inner layer of the right ventricular myocardium, with moderate number in the outer layer of the right and only a few in the inner layer of the left ventricular myocardium. None was detected in the middle layer of the myocardium. Isoproterenol (Iso, 0.5 mol/L) induced more FOSLI cells in the isolated hearts (P<0.01), and they were focally distributed in the outer and inner layer of the left myocardium. Additionally, administration of both 9AC and Iso led to a significant increase in FOS expression by comparision with either 9AC or Iso group (P<0.01). CONCLUSION: The results revealed that 9AC can induce cfos expression in the rat heart, and FOSLI cells showed a regional characteristic distribution. The comparision of cfos expression between 9AC and Iso groups suggests that phosphorylationdephosphorylation mechanism may be implicated in cfos expression induced by 9AC in the rat heart.