尼古丁对缺血心脏去甲肾上腺素释放的影响

目的 探讨尼古丁对缺血后大鼠心脏去甲肾上腺素释放的影响及其机制。方法 以离体大鼠心脏缺血模型。测定尼古丁加入前后的去甲肾上腺素（noradrenaline,NA)，神经肽Y（neuropeptide Y,NPY)及二羟苯基乙二醇（dihydr oxyphenylethyleneglycol,DOPEG)含量的变化，并探讨它们之间的关系。结果 （1）非缺血条件下，低浓度尼古丁灌注液对去甲肾上腺素的释放无明显影响；（2）在缺血10min后，低浓度尼古丁灌注液组较对照组去甲肾上腺素及神经肽Y释放明显增加；（3）缺血20min组与缺血10min组相比，神经肽含量无明显变化，但去甲肾上腺素及DOPEG含量明显上升。结论 尼古丁促进缺血心脏以胞裂（exocytosis)和非胞裂（nonexcytosisin0方式释放去甲肾上腺素。

Effect of nicotine on the release of noradrenaline in the postischemic rat heart

Objective To assess the influence of nicotine on the postischemic rat heart and to investigate its mechanism Method Noradrenaline(NA), neuropeptide Y (NPY) and dihydr oxyphenylethyleneglycol (DOPEG) were determined when low level nicotine solution was applied in isolated perfused rat hearts Results (1)There was no influence on the release of noradrenaline in isolated perfused rat heart in which nicotine of low concentration was applied (2) In consistent with the changes of NA release when nicotine was applied, global ischemic periods of 10 min caused an increase in amount of NPY (3)An obvious increase of NA and NPY was found during postischemic period of 10 min in the rat hearts, while NA and DOPEG increased during postischemic period of 20 min in the rat hearts Conclusion It is suggested that nicotine plays an important role by means of exocytosis and nonexocytosis in the release of NA in the postischemic heart