Demonstration of selective protein kinase C-dependent activation of Src and Lck tyrosine kinases during ischemic preconditioning in conscious rabbits.
Demonstration of selective protein kinase C-dependent activation of Src and Lck tyrosine kinases during ischemic preconditioning in conscious rabbits.
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DOI：
10.1161/01.res.85.6.542
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发表时间：
1999-09
影响因子：
20.1
通讯作者：
P. Ping;J. Zhang;Y. Zheng;R. C. Li;B. Dawn;X. L. Tang;H. Takano;Z. Balafanova;R. Bolli
中科院分区：
文献类型：
--
作者：
P. Ping;J. Zhang;Y. Zheng;R. C. Li;B. Dawn;X. L. Tang;H. Takano;Z. Balafanova;R. Bolli
Src酪氨酸激酶已被证明介导非心肌细胞对应激的细胞反应。然而，心肌缺血对Src酪氨酸激酶的影响尚不清楚。此外，参与缺血预处理（PC）发生的酪氨酸激酶的身份仍然不清楚。在这里，我们提出的第一个证据表明，缺血PC（6个周期的4分钟冠状动脉闭塞和4分钟再灌注）诱导选择性激活的2个成员的Src家族的酪氨酸激酶，Src和Lck，在清醒的兔子的心脏。颗粒部分中Src的活化在缺血性PC后5分钟不明显，但在30分钟变得明显（与对照相比为+119%），而颗粒部分中Lck的活化在缺血性PC后5分钟（与对照相比为+103%）和30分钟（+89%）均明显。在兔心脏中表达的Src酪氨酸激酶的其他5个成员（Fyn、Fgr、Yes、林恩和Blk）的活性不受缺血PC的影响。缺血PC对表皮生长因子受体激酶的活性没有影响，无论是在5分钟还是在30分钟。Src和Lck的激活被酪氨酸激酶抑制剂lavonastin A完全消除，该抑制剂的剂量与先前在同一清醒家兔模型中显示的阻断缺血性PC保护作用的剂量相同，这表明Src和Lck激酶对缺血性PC的发展至关重要。在缺血性PC后5分钟（+72%）和30分钟（+67%），颗粒部分中的蛋白激酶C（PKC）亚型的活性增加。用拉古斯汀A预处理对PKC β的活化没有影响，而用PKC抑制剂白屈菜红碱（以先前已显示阻断缺血性PC的剂量给药）预处理不仅阻断PKC β的活化，而且阻断Src和Lck的活化，表明Src和Lck在缺血性PC的信号级联中是PKC β的下游。这项研究确定了缺血PC信号机制的一个新的组成部分。结果支持的概念，在清醒的兔子，2个特定的成员Src家族的酪氨酸激酶，Src和Lck，发挥了重要作用，在后期PC的发生作为下游元件的PKC介导的信号转导。
Src tyrosine kinases have been shown to mediate cellular responses to stress in noncardiac cells. However, the effect of myocardial ischemia on Src tyrosine kinases is unknown. Furthermore, the identity of the tyrosine kinase(s) involved in the genesis of ischemic preconditioning (PC) remains obscure. Here, we present the first evidence that ischemic PC (6 cycles of 4-minute coronary occlusion and 4-minute reperfusion) induces selective activation of 2 members of the Src family of tyrosine kinases, Src and Lck, in the heart of conscious rabbits. The activation of Src in the particulate fraction was not evident at 5 minutes after ischemic PC but became apparent at 30 minutes (+119% versus control), whereas the activation of Lck in the particulate fraction was apparent both at 5 minutes (+103% versus control) and at 30 minutes (+89%) after ischemic PC. The activity of the other 5 members of the Src tyrosine kinases expressed in the rabbit heart (Fyn, Fgr, Yes, Lyn, and Blk) was not affected by ischemic PC. Ischemic PC had no effect on the activity of epidermal growth factor receptor kinases, either at 5 or at 30 minutes. The activation of Src and Lck was completely abrogated by the tyrosine kinase inhibitor lavendustin A, given at doses that have previously been shown to block the protective effect of ischemic PC in this same conscious rabbit model, suggesting that Src and Lck kinases are essential for the development of ischemic PC. The activity of the epsilon isoform of protein kinase C (PKC) in the particulate fraction increased at 5 minutes (+72%) and at 30 minutes (+67%) after ischemic PC. Pretreatment with lavendustin A had no effect on the activation of PKCepsilon, whereas pretreatment with the PKC inhibitor chelerythrine (given at doses that have previously been shown to block ischemic PC) blocked not only the activation of PKCepsilon but also that of Src and Lck, indicating that Src and Lck are downstream of PKCepsilon in the signaling cascade of ischemic PC. This study identifies a new component of the signaling mechanism of ischemic PC. The results support the concept that, in conscious rabbits, 2 specific members of the Src family of tyrosine kinases, Src and Lck, play an important role in the genesis of late PC by serving as downstream elements of PKC-mediated signal transduction.