四氢生物蝶呤对吸烟者大隐静脉桥内皮功能的影响

目的 观察四氢生物蝶呤(BH4)对吸烟者大隐静脉桥内皮功能的影响.方法 取12例吸烟(实验组)及10例不吸烟(对照组)行冠状动脉旁路移植术患者的大隐静脉.在器官槽中观察经重碳酸盐缓冲液(KH液)、含0.1 mol/L N-硝基-L-精氨酸(L-NNA)或含20 μmol/L BH4的KH液浸泡30 min后,苯肾上腺素(1×10-5 mol/L)及不同浓度(1×10-9～1×10-5mol/L)的非受体介导钙离子载体引发的血管舒缩反应.结果　最大收缩强度各组间差异无统计学意义(P＞0.05).最大舒张反应:经KH液浸泡后实验组低于对照组(29.50±6.22)%比(48.20±7.74)%,P＜0.01];经L-NNA(24.50±5.72)%比(28.80±5.64)%]或BH4(46.40±6.32)%比(50.80±6.91)%]浸泡后两组差异无统计学意义(P＞0.05).结论　吸烟损伤大隐静脉桥内皮源性一氧化氮介导的血管舒张功能,BH4有利于此功能的恢复.

Abstract：

Objective To observe the effect of tetrahydrobiopterin ( BH4 ) on endothelium function of the great saphenous vein from smokers. Methods The rings of great saphenous vein were selected from 22 patients with coronary artery bypass grafting, which including smoking (experimental group,n = 12) and non-smoking (control group,n = 10) patients. After incubation in Krebs-Henseleit (KH), KH plus BH4 (20 μ mol/L) or N-nitro-L-arginine ( L-NNA, 0. 1 mol/L), the vasoconstriction and vasodilatation were induced by phenylephrine (1 × 10-5 mol/L) and non-receptor-mediated calcium ionophore (A23187,1 × 10-9-1 × 10 -5 mol/L) separately in an organ chamber. Results The maximum constriction in all groups had no significant difference ( P ＞ 0. 05 ). The maximum relaxation was significantly decreased in experimental group as compared with control group (29.50 ± 6. 22 ) % vs (48.20 ± 7. 74 ) %, P ＜ 0. 01]after incubation in KH, while there was no significant difference (P ＞ 0. 05 ) after incubation in KH plus L-NNA (24.50±5.72)% vs (28.8 ±5.64)%] or BH4(46.40 ±6.32)% vs (50.80±6.91)%].Conclusion Smoking impairs the relaxation function mediated by endothelium-derived nitric oxide in great saphenous, which may be restored by BH4.

Effect of tetrahydrobiopterin on endothelium function of the great saphenous vein from smokers

Objective To observe the effect of tetrahydrobiopterin ( BH4 ) on endothelium function of the great saphenous vein from smokers. Methods The rings of great saphenous vein were selected from 22 patients with coronary artery bypass grafting, which including smoking (experimental group,n = 12) and non-smoking (control group,n = 10) patients. After incubation in Krebs-Henseleit (KH), KH plus BH4 (20 μ mol/L) or N-nitro-L-arginine ( L-NNA, 0. 1 mol/L), the vasoconstriction and vasodilatation were induced by phenylephrine (1 × 10-5 mol/L) and non-receptor-mediated calcium ionophore (A23187,1 × 10-9-1 × 10 -5 mol/L) separately in an organ chamber. Results The maximum constriction in all groups had no significant difference ( P ＞ 0. 05 ). The maximum relaxation was significantly decreased in experimental group as compared with control group (29.50 ± 6. 22 ) % vs (48.20 ± 7. 74 ) %, P ＜ 0. 01]after incubation in KH, while there was no significant difference (P ＞ 0. 05 ) after incubation in KH plus L-NNA (24.50±5.72)% vs (28.8 ±5.64)%] or BH4(46.40 ±6.32)% vs (50.80±6.91)%].Conclusion Smoking impairs the relaxation function mediated by endothelium-derived nitric oxide in great saphenous, which may be restored by BH4.