中文摘要：

目的：探讨过氧化氢（H2O2）和11，12-环氧二十碳三烯酸（11，12-EET）在内皮依赖性超极化因子（endothelium—dependent hyperpolarizing factor，EDHF）介导的基底动脉舒张中的作用。方法：采用离体血管舒缩功能测定实验，检测乙酰胆碱（ACh）、H2O2、11，12-EET及过氧化氢酶（CAT）等对大鼠离体脑基底动脉血管环的舒张作用。结果：在30mmol／L的KCl预收缩的大鼠脑基底动脉环上，ACh可产生浓度依赖性的舒张作用；血管用NO合酶抑制剂（L-NAME，3×10^5 mol／L）和前列环素（PGI2）合酶抑制剂（Indo，10^-5mol／L）预处理后，ACh对基底动脉仍存在部分舒张作用，即非NO和非PGI2介导的舒张。应用L-NAME和Indo后，11，12-EET对大鼠基底动脉无明显的舒张作用，H2O2仅有轻微舒张作用，CAT对ACh介导的非NO和非PGI2反应没有影响。结论：在大鼠基底动脉中ACh介导的EDHF反应即非NO和非PGI2介导的舒张中不涉及H2O2和11，12-EET。

英文摘要：

AIM： To study the effects of Hydrogen Peroxide（ H2O2 ） and 11,12-epoxyeicosatrienoic acid （11, 12-EET）on EDHF-mediated relaxation in the rat basilar arteries. METHODS： The relaxant effects of acetylcholine （ACh）, H2O2, 11, 12 EET, and catalase （CAT） on rat arteria basilaris in vitro were detected by vasomotoricity experiment in vitro. RESULTS. In the rat basilar arteries, precon- stricted by 30 mmol/L KCl in vitro , ACh（10^-7 -10 ^-4.5 mol/L） had the concentration-depend- ent relaxation effect. 3× 10^-5mol/L Nω-nitro-L -arginine-methyl-ester （ L-NAME ） and 10 ^-5 mol/L indomethacin （Indo） could partly inhibit the relaxation effect of ACh to the rat basilar arteries, but non-No/non-PGI2-mediated relaxa- tion was still significant （P〈0.01 vs Vehicle）. After using L -NAME and Indo, 11,12-EET didn ＇t produce relaxation effect in rat basilar arteries and H2O2 has little relaxation effect. CAT could not inhibit the relaxation effects of ACh. CON- CLUSION. Our data suggest that H2O2 and 11, 12-EET may not involve EDHF-mediated relaxa tion to ACh in the rat basilar arteries.