Protein kinase C regulates smooth muscle tension in guinea-pig trachea and ileum.
Protein kinase C regulates smooth muscle tension in guinea-pig trachea and ileum.
复制标题
蛋白激酶 C 调节豚鼠气管和回肠的平滑肌张力。
DOI：
10.1016/0014-2999(86)90153-6
复制
发表时间：
1986
影响因子：
5
通讯作者：
Snyder,SH
中科院分区：
文献类型：
--
作者：
Menkes,H;Baraban,JM;Snyder,SH
为了探讨蛋白激酶C在平滑肌中的作用，我们在豚鼠气管环和回肠条中检测了蛋白激酶C的强效激活剂佛波酯的作用。在气管环中，磷酸氢酚-12,13-二乙酸酯（PDA）和12-脱氧磷酸氢酚-13-异丁酸酯（DPB）都是蛋白激酶C的强效刺激物，可产生浓度依赖性的、可逆的静息气管张力松弛，而磷酸氢酚作为一种无活性类似物是无效的。PDA还能逆转由乙醇、血清素、前列腺素f2 α和前列腺素D2产生的收缩。与它们抑制激动剂诱导的收缩的能力相反，PDA和DPB极大地放大了KCl去极化浓度（59 mM）所产生的收缩。钙通道阻滞剂维拉帕米、硝苯地平和地尔硫卓阻断KCl和PDA产生的收缩，这表明在去极化条件下，PDA与细胞内钙增加协同作用，增强肌肉收缩。类似的双相反应在豚鼠回肠条中引起。这些结果表明，除了增强细胞内钙在产生收缩中的作用外，蛋白激酶C还可以激活限制细胞反应的反馈机制。
To explore the function of protein kinase C in smooth muscle, the effects of phorbol esters, potent activators of protein kinase C, were examined in guinea-pig tracheal rings and ileal strips. In tracheal rings, phorbol-12,13-diacetate (PDA) and 12-deoxyphorbol-13-isobutyrate (DPB), both potent stimulants of protein kinase C, produce a concentration dependent, reversible relaxation of resting tracheal tension, whereas phorbol, an inactive analogue is ineffective. PDA also reverses contractions produced by carbachol, serotonin, prostaglandin F2αand prostaglandin D2. In contrast to their ability to inhibit agonist induced contractions, PDA and DPB greatly amplify the constriction produced by a depolarizing concentration of KCl (59 mM). The calcium channel blockers verapamil, nifedipine and diltiazem block the constriction produced by KCl and PDA suggesting that under depolarizing conditions, PDA synergizes with increased intracellular calcium to potentiate muscle contraction. Similar biphasic responses to phorbol esters are elicited in strips of guinea-pig ileum. These results indicate that in addition to enhancing the actions of intracellular calcium in producing contraction, protein kinase C can also activate feedback mechanisms which limit cellular responses.