Department of Environmental and Preventive Medicine, Hyogo College of Medicine, Nishinomiya, Hyogo 663-8501, Japan.
Eur J Pharmacol. 2010 Mar 10;629(1-3):1-6. doi: 10.1016/j.ejphar.2009.11.054. Epub 2009 Dec 1.
The purpose of this study was to determine whether expression of inducible nitric oxide synthase (iNOS) is altered in vascular smooth muscle cells of type 2 diabetes rats. We used cultured aortic smooth muscle cells (ASMCs) isolated from male Goto-Kakizaki diabetes rats (G-K rats) aged 27-28weeks and age-matched Wistar rats (control rats). iNOS and extracellular signal-regulated kinase (ERK) were evaluated by immunoblot and/or immunochemical analyses, and NO production was evaluated by measuring NO(X) (NO(2) and NO(3)). Expression of iNOS was not detected in ASMCs of either G-K or control rats under a resting condition. Stimulation with interleukin-1beta (IL-1beta) induced iNOS expression, which was much greater in ASMCs from G-K rats than in ASMCs from control rats. When ASMCs were stimulated with IL-1beta, the number of iNOS-immunoreactive ASMCs from G-K rats increased more prominently than did the number of such ASMCs from control rats. IL-1beta-induced NO production was also much greater in ASMCs from G-K rats than in those from control rats. Both IL-1beta-induced iNOS expression and NO production in ASMCs of G-K and control rats were markedly reduced in the presence of an ERK inhibitor, U0126 or PD98059. Both basal and IL-1beta-stimulated levels of ERK activity were significantly higher in ASMCs from G-K rats than in ASMCs from control rats. The results suggest that iNOS induction is enhanced in cultured ASMCs from G-K rats and that this enhancement is associated with increased ERK activity.
本研究旨在探讨 2 型糖尿病大鼠血管平滑肌细胞中诱导型一氧化氮合酶（iNOS）的表达是否发生改变。我们使用 27-28 周龄雄性 Goto-Kakizaki 糖尿病大鼠（G-K 大鼠）和年龄匹配的 Wistar 大鼠（对照组大鼠）分离培养的主动脉平滑肌细胞（ASMCs）。通过免疫印迹和/或免疫组织化学分析评估 iNOS 和细胞外信号调节激酶（ERK）的表达，通过测量 NO(X)（NO2 和 NO3）评估 NO 生成。在静息状态下，G-K 或对照组大鼠的 ASMCs 中均未检测到 iNOS 的表达。白细胞介素-1β（IL-1β）刺激诱导 iNOS 表达，G-K 大鼠的 ASMCs 表达水平明显高于对照组大鼠。当 ASMCs 受到 IL-1β刺激时，G-K 大鼠的 iNOS 免疫反应性 ASMC 数量比对照组大鼠增加得更为显著。G-K 大鼠的 ASMCs 中由 IL-1β诱导的 NO 生成也明显高于对照组大鼠。在 ERK 抑制剂 U0126 或 PD98059 存在的情况下，G-K 和对照组大鼠的 ASMCs 中，IL-1β诱导的 iNOS 表达和 NO 生成均明显减少。G-K 大鼠的 ASMCs 中 ERK 活性的基础水平和 IL-1β刺激水平均明显高于对照组大鼠。结果表明，G-K 大鼠培养的 ASMCs 中 iNOS 的诱导增强，这种增强与 ERK 活性的增加有关。
