哇巴因信号的传递及其对细胞生长和死亡的影响

哇巴因(ouabain)是能抑制Na+,K+ ATPase活性的强心甾类物质,在Na+,K+ ATPaseα亚单位位于细胞膜外侧有 1个ouabain特异性结合位点,ouabain结合时,活化胞浆中具酪氨酸蛋白激酶活性的Src,形成Na+,K+ ATPase Src复合物,作为一个活化的“二元”受体,介导信号传递。oua bain对细胞生长和死亡起重要调节作用。ouabain介导细胞发生杂合性死亡,即同一细胞兼具细胞肿胀、细胞器溶解等坏死特征和核凝集、DNA裂解、caspase级联反应等凋亡特征,对于细胞死亡的认识具有重要意义。

The ouabain signal transduction and its role in cell growth and death

The ouabain is a member of the cardiotonic steroids (CT S) that specifically bind to Na ,K -ATPase. Binding of ouabain to Na ,K -ATPase causes rapid activation of Src family kinases, and forms a Na ,K -ATPase-Src complex as a active binary receptor to phosphorylate and assem ble other proteins into different signaling modules.Oubain stimulates hypertroph ic growth in cardiac myocytes and proliferation in smooth muscle cells, it also induces apoptosis and a newly recognized "hybrid cell death" of concurrent apopt osis and necrosisin the same cells.