Veille J C, Li P, Eisenach J C, Massmann A G, Figueroa J P
Department of Obstetrics and Gynecology, Bowman Gray School of Medicine, Winston-Salem, NC 27157, USA.
Am J Obstet Gynecol. 1996 Mar;174(3):1043-9. doi: 10.1016/s0002-9378(96)70348-4.
Our purpose was to determine whether estrogen alters the relaxation responses to bradykinin and superoxide dismutase of the uterine and renal arteries and to determine the role of nitric oxide in that response.
Ten nulliparous, ovariectomized nonpregnant sheep received either estradiol-17beta or vehicle solution. In vitro studies evaluating vasorelaxation were done with either bradykinin or superoxide dismutase. The nitric oxide inhibitor nomega-nitro-L-arginine methyl ester was used to determine the role of nitric oxide in this process. Nitric oxide synthase activity was assessed by measuring citrulline generation.
We found a dose dependency of relaxation to bradykinin and superoxide dismutase. Estrogen enhanced this response in uterine arteries. Estrogen increased citrulline generation in uterine but not renal arteries. Nomega-nitro-L-arginine methyl ester blocked relaxation responses and citrulline generation in both arteries.
In nonpregnant sheep we found that nitric oxide release and nitric oxide synthase activity is enhanced by estrogen in the uterine arteries but not in the renal arteries. Increases in nitric oxide synthase activity may be important in the hyperemic response of the uterus during estrus.
我们的目的是确定雌激素是否会改变子宫和肾动脉对缓激肽和超氧化物歧化酶的舒张反应，并确定一氧化氮在该反应中的作用。
十只未生育、卵巢切除的非妊娠绵羊接受了雌二醇-17β或赋形剂溶液。使用缓激肽或超氧化物歧化酶进行了评估血管舒张的体外研究。使用一氧化氮抑制剂Nω-硝基-L-精氨酸甲酯来确定一氧化氮在此过程中的作用。通过测量瓜氨酸生成来评估一氧化氮合酶活性。
我们发现对缓激肽和超氧化物歧化酶的舒张存在剂量依赖性。雌激素增强了子宫动脉的这种反应。雌激素增加了子宫动脉而非肾动脉中的瓜氨酸生成。Nω-硝基-L-精氨酸甲酯阻断了两条动脉的舒张反应和瓜氨酸生成。
在非妊娠绵羊中，我们发现雌激素增强了子宫动脉而非肾动脉中的一氧化氮释放和一氧化氮合酶活性。一氧化氮合酶活性的增加可能在发情期子宫的充血反应中起重要作用。
