Essential activation of PKC-δ in opioid-initiated cardioprotection
Essential activation of PKC-δ in opioid-initiated cardioprotection
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DOI：
10.1152/ajpheart.2001.280.3.h1346
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发表时间：
2001-03-01
影响因子：
4.8
通讯作者：
Gross, GJ
中科院分区：
文献类型：
--
作者：
Fryer, RM;Wang, YG;Gross, GJ
δ（1）-阿片受体的刺激对缺血心肌具有心脏保护作用。在大鼠冠状动脉闭塞30分钟再灌注2小时的心肌梗死模型中，我们检测了TAN-67或D-Ala（2）-D-Leu（5）-脑啡肽（DADLE）刺激δ-阿片受体后蛋白激酶C（PKC）的作用。通过四氮唑染色确定肿瘤大小（IS），并表示为风险面积（IS/AAR）的百分比。进行缺血和再灌注的对照动物的IS/AAR为59.9 +/-1.8。缺血前给予DADLE和TAN-67显著降低IS/AAR（分别为36.9 ± 3.9和36.7 ± 4.7）。δ（1）-选择性阿片拮抗剂7-亚苄基纳洛酮（BNTX）可消除TAN-67诱导的心脏保护作用（54.4 +/- 1.3）。用PKC拮抗剂白屈菜红碱治疗完全消除了DADLE-（61.8 +/- 3.2）和TAN-67诱导的心脏保护作用（55.4 +/- 4.0）。类似地，PKC拮抗剂GF 109203 X完全消除了TAN-67诱导的心脏保护作用（54.6 +/- 6.6）。在用盐水、白屈菜红碱、BNTX或TAN-67和白屈菜红碱或BNTX在TAN-67存在下处理15分钟后获得的心肌活检中，用针对特异性PKC亚型的抗体进行免疫荧光染色。TAN-67诱导PKC-α易位至肌膜，PKC-β（1）易位至细胞核，PKC-δ易位至线粒体，PKC-β易位至闰盘和线粒体。白屈菜红碱和BNTX可抑制TAN-67处理大鼠的PKC转位。为了更仔细地研究这些亚型在心脏保护中的作用，我们使用了PKC-δ选择性拮抗剂rottlerin。Rottlerin消除阿片类药物诱导的心脏保护（48.9 +/- 4.8）和PKC-δ易位，而不影响PKC-α，-β（1）或-β（2）的易位。这些结果表明，PKC-δ是一个关键的第二信使δ（1）-阿片受体刺激大鼠的心脏保护作用。
Stimulation of the delta (1)-opioid receptor confers cardioprotection to the ischemic myocardium. We examined the role of protein kinase C (PKC) after delta -opioid receptor stimulation with TAN-67 or D-Ala(2)-D-Leu(5)-enkephalin (DADLE) in a rat model of myocardial infarction induced by a 30-min coronary artery occlusion and 2-h reperfusion. Infarct size (IS) was determined by tetrazolium staining and expressed as a percentage of the area at risk (IS/AAR). Control animals, subjected to ischemia and reperfusion, had an IS/AAR of 59.9 +/- 1.8. DADLE and TAN-67 administered before ischemia significantly reduced IS/AAR (36.9 +/- 3.9 and 36.7 +/- 4.7, respectively). The delta (1)-selective opioid antagonist 7-benzylidenenaltrexone (BNTX) abolished TAN-67-induced cardioprotection (54.4 +/- 1.3). Treatment with the PKC antagonist chelerythrine completely abolished DADLE- (61.8 +/- 3.2) and TAN-67-induced cardioprotection (55.4 +/- 4.0). Similarly, the PKC antagonist GF 109203X completely abolished TAN-67-induced cardioprotection (54.6 +/- 6.6). Immunofluorescent staining with antibodies directed against specific PKC isoforms was performed in myocardial biopsies obtained after 15 min of treatment with saline, chelerythrine, BNTX, or TAN-67 and chelerythrine or BNTX in the presence of TAN-67. TAN-67 induced the translocation of PKC-alpha to the sarcolemma, PKC-beta (1) to the nucleus, PKC-delta to the mitochondria, and PKC-epsilon to the intercalated disk and mitochondria. PKC translocation was abolished by chelerythrine and BNTX in TAN-67-treated rats. To more closely examine the role of these isoforms in cardioprotection, we utilized the PKC-delta selective antagonist rottlerin. Rottlerin abolished opioid-induced cardioprotection (48.9 +/- 4.8) and PKC-delta translocation without affecting the translocation of PKC-alpha,- beta (1), or -epsilon. These results suggest that PKC-delta is a key second messenger in the cardioprotective effects of delta (1)-opioid receptor stimulation in rats.