邻苯三酚与亚甲蓝舒张大鼠肠系膜动脉的不同机制(英文)

Mechanisms of relaxation by pyrogallol and methylthioninium chloride in perfused rat mesenteric artery

在去内皮肠系膜血管,邻苯三酚与亚甲蓝产生浓度依赖性舒张,SOD可取消邻苯三酚对TNS所致缩血管效应的抑制作用,但不影响亚甲蓝的效应。邻苯三酚与亚甲蓝的舒血管效应不被过氧化氢酶、去铁胺、吲哚美辛和辣椒素所影响。结果提示,邻苯三酚的舒血管效应是其产生超氧阴离子所致,而亚甲蓝的效应为直接作用于血管平滑肌。

In perfused rat mesenteric arteries without endothelium, pyrogallol (Pyr ) or methylthioninium chloride (methyiene blue, Met) produced a concentration-dependent relaxation. Superoxide dismutase abolished inhibition by Pyr, but not Met, of vasoconstrictor responses to transmural nerve stimulation (TNS). Neither catalase nor deferoxamine had any effect on vasodilator responses to Pyr or Met. Vasodilator responses to Pyr were unaltered by N-nitro-L-arginine methyl ester (L-NAME), indomethacin, or capsaicin. Similarly, the relaxing effect of Met was unaffected by indomethacin or capsaicin. These findings suggest that vasodilator responses to Pyr may be due to endothelial-independent generation of superoxide anion. In contrast the relaxation produced by Met appears to be due to a direct action on vascular smooth muscle independent of superoxide anion generation.