电剌激及心肌缺血所致豚鼠心脏神经肽Y释放变化的研究

电剌激豚鼠心脏左星状交感神经节，可引起钙依赖性的神经肽Ｙ（ＮＰＹ）胞外释放，缺血１０ｍｉｎ后行电刺激（Ｓ２），与对照期（Ｓ１）比较，ＮＰＹ释放无明显变化，缺血２０ｍｉｎ后行电剌激，ＮＰＹ释放受到一定程度的抑制，（Ｓ２／Ｓ１：０．７２，Ｐ＜０．０５），而再灌注５ｍｉｎ后行电剌激ＮＰＹ释放抑制作用逐步消失，与Ｓ１比较，已无明显减少（Ｓ２／Ｓ１；１．０１，Ｐ＞０．０５）。仅缺血无电剌激几乎不引起ＮＰＹ释放。这些结果提示，电剌激交感神经节可致ＮＰＹ呈现一种钙依赖性出胞释放，缺血早期ＮＰＹ释放受到某些代谢产物抑制，恢复再灌注后，代谢产物逐步冲洗出，抑制作用也随之消失。

A STUDY ON THE CHANGE OF MYOCARDIAL NEUROPEPTIDE Y RELEASE INDUCED BY ELECTRIC STIMULATION AND MYOCARDIAL ISCHEMIA IN GUINEA PIG HEART

Electrical stimulation of the left stellate ganglion in guinea pig heart evoked a calcium-dependent, exocytotic release of neuropeptide Y (NPY). Stimulation after 10 min of global ischemia (S2), compared with control period stimulation (S1), had no signifcant effect on the NPY release. The release of NPY produced by the same stimulation fter 20 min of ischemia was inhibited to certain extent (S2/S1: 0.72, P<0.05),whereas the inhibition of NPY release disappeared after 5 min of reper fusion (with a S2/S1 of 1.01). Ischemia alone, without electric stimulation, did not apparently induce NPY release, suggesting that electrical Stimulation may induce a calcium-dependent, exocytotic release of NPY. It is further suggested that the inhibion of NPY release may be produced by some metubolites and the abolishment of the inhibion after reperfusionmay be due to washout of the metubolites.