Mayhan W G, Didion S P, Patel K P
Department of Physiology and Biophysics, University of Nebraska Medical Center, Omaha, USA.
J Cereb Blood Flow Metab. 1996 May;16(3):500-6. doi: 10.1097/00004647-199605000-00017.
The goal of this study was to test the hypothesis that administration of L-arginine, a substrate for the synthesis of nitric oxide, restores endothelium-dependent dilatation of the basilar artery during diabetes mellitus. We measured the diameter, of the basilar artery in vivo in nondiabetic and diabetic (streptozotocin; 50-60 mg/kg i.p.) rats in response to endothelium-dependent agonists (acetylcholine and bradykinin) and an endothelium-independent agonist (nitroglycerin) before and during application of L-arginine. Topical application of acetylcholine (1.0 and 10 muM) and bradykinin (1.0 and 10 microM) produced dilatation in nondiabetic rats of the basilar artery which was impaired in diabetic rats. Topical application of nitroglycerin (0.1 and 1.0 microM) produced similar dilatation of the basilar artery in nondiabetic and diabetic rats. Topical application of L-arginine (0.1 and 3 mM) did not enhance dilatation of the basilar artery in response to acetylcholine and bradykinin in diabetic rats. Thus, impairment of dilatation of the basilar artery in diabetic rats in response to acetylcholine and bradykinin appears to be related to a mechanism unrelated to the availability of L-arginine for nitric oxide synthase.
给予一氧化氮合成底物L-精氨酸可恢复糖尿病期间基底动脉的内皮依赖性舒张功能。我们在给予L-精氨酸之前和期间，测量了非糖尿病和糖尿病（链脲佐菌素；腹腔注射50-60mg/kg）大鼠体内基底动脉对内皮依赖性激动剂（乙酰胆碱和缓激肽）和内皮非依赖性激动剂（硝酸甘油）的反应时的直径。局部应用乙酰胆碱（1.0和10μM）和缓激肽（1.0和10μM）可使非糖尿病大鼠的基底动脉舒张，而糖尿病大鼠的这种舒张功能受损。局部应用硝酸甘油（0.1和1.0μM）可使非糖尿病和糖尿病大鼠的基底动脉产生相似的舒张。局部应用L-精氨酸（0.1和3mM）并未增强糖尿病大鼠基底动脉对乙酰胆碱和缓激肽的舒张反应。因此，糖尿病大鼠基底动脉对乙酰胆碱和缓激肽的舒张功能受损似乎与一氧化氮合酶可利用的L-精氨酸无关的机制有关。
