Nelson S H, Steinsland O S, Suresh M S, Lee N M
Department of Anesthesiology, The University of Texas Medical Branch, Galveston 77555, USA.
Hum Reprod. 1998 May;13(5):1361-7. doi: 10.1093/humrep/13.5.1361.
The influence of pregnancy on the dilator effects of acetylcholine in the isolated human uterine artery was investigated. Acetylcholine (0.1 nM to 0.1 microM) produced concentration- and endothelium-dependent relaxation of norepinephrine (3 microM)-induced contraction. The relaxation was greater in arteries from pregnant patients (P arteries) than from non-pregnant patients (NP arteries). The maximal relaxation was 53.5+/-3.4% (n=21) in P arteries and 23.5+/-2.5% (n=35) in NP arteries. In both P and NP arteries the cholinergic relaxation was increased in the presence of superoxide dismutase and greatly reduced in the presence of the nitric oxide synthase inhibitors, NG-mono-methyl L-arginine (L-NMMA) and L-nitro-arginine-methylester (L-NAME). The effect of these nitric oxide synthase inhibitors was reversed by L-arginine. We conclude that pregnancy enhances acetylcholine-induced nitric oxide synthesis and release in the human uterine artery.
研究了妊娠对人离体子宫动脉中乙酰胆碱舒张作用的影响。乙酰胆碱（0.1 nM至0.1 microM）可产生浓度和内皮依赖性的去甲肾上腺素（3 microM）诱导收缩的舒张作用。来自妊娠患者的动脉（P动脉）的舒张作用比非妊娠患者的动脉（NP动脉）更强。P动脉的最大舒张率为53.5±3.4%（n = 21），NP动脉为23.5±2.5%（n = 35）。在P和NP动脉中，超氧化物歧化酶存在时胆碱能舒张作用增强，而一氧化氮合酶抑制剂NG-单甲基-L-精氨酸（L-NMMA）和L-硝基精氨酸甲酯（L-NAME）存在时舒张作用大大减弱。L-精氨酸可逆转这些一氧化氮合酶抑制剂的作用。我们得出结论，妊娠可增强人子宫动脉中乙酰胆碱诱导的一氧化氮合成和释放。
