Ma Ji, Kishida Shinya, Wang Guo Qin, Meguro Kentarou, Imuta Hiroyuki, Oonuma Hitoshi, Iida Haruko, Jo Taisuke, Takano Haruhito, Morita Toshihiro, Nagai Ryozo, Nakajima Toshiaki
Department of Cardiovascular Medicine and Respiratory Medicine, University of Tokyo, Tokyo, Japan.
J Cardiovasc Pharmacol. 2006 Feb;47(2):314-21. doi: 10.1097/01.fjc.0000205497.90765.b0.
Overproduction of nitric oxide by inducible nitric oxide synthase contributes to the progression of cardiovascular disease. We investigated the effects of azelnidipine and other Ca2+-channel blockers on nitric oxide production by cultured aortic smooth muscle cells isolated from Wistar rats and human umbilical vein endothelial cells (HUVECs), using the Griess reaction and oxyhemoglobin method. Release of lactic dehydrogenase (LDH) was measured to evaluate cell damage, and immunohistochemistry was performed to examine the expression of inducible nitric oxide synthase and nitrotyrosine protein. Azelnidipine and other Ca2+-channel blockers inhibited the release of nitric oxide induced by lipopolysaccharide plus interferon-gamma. Azelnidipine inhibited it most potently among the Ca2+-channel blockers tested (azelnidipine, amlodipine, nifedipine, diltiazem, verapamil, and nicardipine) at a concentration of 10 microM. Longer stimulation with these agents induced the expression of inducible nitric oxide synthase and nitrotyrosine, with an increase of lactic dehydrogenase release, whereas azelnidipine suppressed these changes. In human umbilical vein endothelial cells, azelnidipine enhanced basal nitric oxide production by endothelial nitric oxide synthase. In conclusion, azelnidipine potently inhibited the induction of inducible nitric oxide synthase and then nitric oxide production in vascular smooth muscle cells, while enhancing constitutive nitric oxide production by endothelial cells. Azelnidipine may inhibit nitrotyrosine expression and cell damage caused by overproduction of nitric oxide, suggesting a mechanism for its cardiovascular protective effect.
诱导型一氧化氮合酶产生过量一氧化氮会促使心血管疾病的发展。我们使用格里斯反应和氧合血红蛋白法，研究了阿折地平及其他钙通道阻滞剂对从Wistar大鼠分离的培养主动脉平滑肌细胞和人脐静脉内皮细胞（HUVECs）一氧化氮生成的影响。通过测量乳酸脱氢酶（LDH）的释放来评估细胞损伤，并进行免疫组织化学检测诱导型一氧化氮合酶和硝基酪氨酸蛋白的表达。阿折地平和其他钙通道阻滞剂抑制了脂多糖加干扰素-γ诱导的一氧化氮释放。在测试的钙通道阻滞剂（阿折地平、氨氯地平、硝苯地平、地尔硫䓬、维拉帕米和尼卡地平）中，阿折地平在10微摩尔浓度时抑制作用最强。用这些药物进行更长时间的刺激会诱导诱导型一氧化氮合酶和硝基酪氨酸的表达，同时乳酸脱氢酶释放增加，而阿折地平可抑制这些变化。在人脐静脉内皮细胞中，阿折地平增强了内皮型一氧化氮合酶产生的基础一氧化氮。总之，阿折地平能有效抑制血管平滑肌细胞中诱导型一氧化氮合酶的诱导及随后的一氧化氮生成，同时增强内皮细胞组成型一氧化氮的生成。阿折地平可能抑制硝基酪氨酸表达和一氧化氮过量产生所导致的细胞损伤，这提示了其心血管保护作用的机制。
