Division of Experimental Vascular Research, Institute of Clinical Science in Lund, Lund University, Sweden.
Eur J Pharmacol. 2010 Jul 10;637(1-3):148-54. doi: 10.1016/j.ejphar.2010.04.006. Epub 2010 Apr 23.
Vascular smooth muscle cells (SMC) endothelin type B (ET(B)) receptor upregulation results in strong vasoconstriction and reduction of local blood flow. We hypothesizes that the underlying molecular mechanisms involve transcriptional factor nuclear factor-kappaB (NF-kappaB) pathway. ET(B) receptor upregulation and activation of NF-kappaB were studied at functional contraction (in vitro myograph), mRNA (real-time PCR), and protein (Western blot and immunocytochemistry) levels during organ culture of rat mesenteric arteries. Organ culture of the artery segments induced a time-dependent strong contractile response to sarafotoxin 6c in parallel with enhanced expression of ET(B) receptor mRNA and protein in the SMC. Western blot experiments demonstrated that phosphorylation of NF-kappaB p65 was time-dependently induced during organ culture starting at 1h. In addition, cytoplasmic IkB degradation occurred in parallel with nuclear NF-kappaB accumulation following organ culture. The enhanced expression of ET(B) receptor protein was apparent at 3h in the SMC and while enhanced ET(B) receptor-mediated contractions occurred first at 12h. The specific IkappaB inhibitors, IMD-0354 (N-(3,5-Bis-trifluoromethylphenyl)-5-chloro-2-hydroxybenzamide) and Wedelolactone (7-Methoxy-5,11,12-trihydroxycoumestan), abolished the organ culture induced ET(B) receptor upregulation. The intracellular NF-kappaB pathway is involved in the process of induced expression of vascular SMC ET(B) receptors.
血管平滑肌细胞（SMC）内皮素 B 型（ET（B））受体上调导致强烈的血管收缩和局部血流量减少。我们假设潜在的分子机制涉及转录因子核因子-κB（NF-κB）途径。在大鼠肠系膜动脉器官培养过程中，研究了 ET（B）受体上调和 NF-κB 的激活在功能收缩（体外肌描记器）、mRNA（实时 PCR）和蛋白质（Western blot 和免疫细胞化学）水平上的作用。动脉段的器官培养诱导了对沙夫托毒素 6c 的时间依赖性强烈收缩反应，同时 SMC 中 ET（B）受体 mRNA 和蛋白的表达增强。Western blot 实验表明，NF-κB p65 的磷酸化在器官培养开始后 1h 内呈时间依赖性诱导。此外，细胞质 IkB 降解与器官培养后核 NF-κB 积累平行发生。SMC 中 ET（B）受体蛋白的增强表达在 3h 时明显，而增强的 ET（B）受体介导的收缩首先在 12h 时发生。特定的 IkappaB 抑制剂 IMD-0354（N-（3,5-双三氟甲基苯基）-5-氯-2-羟基苯甲酰胺）和 Wedelolactone（7-甲氧基-5,11,12-三羟基香豆素）消除了器官培养诱导的 ET（B）受体上调。细胞内 NF-κB 途径参与诱导血管 SMC ET（B）受体表达的过程。
