L－NNA和还原型Hb对SHRsp肠系膜动脉内皮依赖性舒张的影响  

EFFECTS OF N￣G-NITRO-L-ARGININE AND REDUCED HEMOGLOBIN ON ENDOTHELIUM-DEPENDENT RELAXATION OF MESENTERIC ARTERY IN SHRsp

作　　者：郑永芳[1] 张翠华[1] 王晓芳[1] 

机构地区：[1]中国医学科学院基础医学研究所生理研究室

出　　处：《生理学报》1994年第6期568-574,共7页Acta Physiologica Sinica

基　　金："八五"国家科技攻关专题资助

摘　　要：我们以往的工作证实成年自发高血压大鼠（ＳＨＲ与ＳＨＲｓｐ）肠系膜动脉由乙酰胆碱引起的内皮依赖性舒张（ＥＤＲ）减弱。为进一步探讨ＥＤＲ减弱的机制，本文观察了一氧化氮（ＮＯ）合成酶抑制剂左旋硝基精氨酸（Ｌ－ＮＮＡ）及ＥＤＲＦ灭活剂还原型血红蛋白（ＲＨｂ）对卒中易感型自发高血压大鼠（ＳＨＲｓｐ）与常压对照（ＷＫＹ）大鼠肠系膜动脉ＡＣｈ内皮依赖性舒张（ＥＤＲ）的影响。发现Ｌ－ＮＮＡ（１０（－３）ｍｏｌ／Ｌ）可使ＳＨＲｓｐ弱于ＷＫＹ的ＡＣｈＥＤＲ（１０（－８）－１０（－５）ｍｏｌ／Ｌ）的差异消失，ＲＨｂ（１０（－５）ｍｏｌ／Ｌ）则仅在１０（－７）－１０（－８）ｍｏｌ／ＬＡＣｈ时使ＳＨＲ（ｓｐ）肠系膜动脉ＥＤＲ弱于ＷＫＹ的差异消失。将ＷＫＹ在加入Ｌ－ＮＮＡ后的与加入ＲＨｂ后的ＡＣｈ（１０（－８）－１０（－５）ｍｏｌ／Ｌ）ＥＤＲ进行比较，无显著差异。而将ＳＨＲｓｐ在Ｌ－ＮＮＡ后的与ＲＨｂ后的ＡＣｈ（１０（－８）－１０（－６）ｍｏｌ／Ｌ）ＥＤＲ进行比较，则有显著差异。并且，ＳＨＲｓｐ的有内皮肠系膜动脉条对ＲＨｂ的敏感性与ＷＫＹ接近，对Ｌ－ＮＮＡ的敏感性则低于ＷＫＹ。表明高血压时肠系膜动脉内皮依赖性舒张减弱中，ＥＤＲＦ机制与?It was verified in our previous study that endothelium-dependent relaxation(EDR)in the mesenteric artery strip of adult spontaneously hypertensive rats(SHR and SHRsp)was decreased upon addition of acetylcholine(ACh).In order to explore further the mechanism of this decrease of EDR,foe effects of NG-nitro-L-arginine(LNNA)(a NO synthase inhibitor)and reduced hemoglobin(RHb)(a scavenger of EDRF)on this ACh EDR were investigated in both stroke--prone SHR(SHRsp)and control WKYs.Our results showed that the difference of EDR(ACh 10-8-10-5 mol/L)between SHRsp and WKY disappeared in the presence of L--NNA(10--3 mol/L),but addition of RHb (10-5 mol/L)would abolish such a difference only at Ach 10(-7)-10(-8)mol/L.In comparision to changes of EDR(ACh 10--8--10--5 mol/L)between post L-NNA and post RHb in WKY and in SHRsp, no significant difference was found in WKY,but significant difference was found in SHRsp.And also,it appeared that the sensitivity of intact endothelium mesenteric artery of SHRsp to RHb was similar to WKY,but that to L--NNA is lower than that of WKY.\Consequently it is considered that in the attentuation of EDR in hypertensive visceral vessels,the EDRF mechanism and endothelial L-arg--NO pathway are not identical.

关 键 词：高血压 左旋硝基精氨酸 血管内皮 舒张因子 

分 类 号：R544.102[医药卫生—心血管疾病]