Thomas G, Ramwell P W
Georgetown University Medical Center, Department of Physiology & Biophysics, Washington, D.C. 20007.
Biochem Biophys Res Commun. 1988 Jul 15;154(1):332-8. doi: 10.1016/0006-291x(88)90689-4.
Benzoyl derivatives of L-arginine, unlike arginine, elicited relaxation of pre-contracted rat aortic rings in a concentration dependent manner. The most potent relaxing agent was N-alpha-benzoyl-L-arginine ethyl ester. The relaxation was abolished by methylene blue, but not by indomethacin. When incubated with rat aortic rings, the benzoyl derivatives exhibited colorimetric reactions characteristic of citrulline and nitrite ion. This indicates the presence of a peptidyl arginine deiminase like activity in rat aorta. Citrulline had no vasodilatory property. The other product of the iminase reaction is ammonia which through oxygenase pathway may generate nitric oxide, the proposed endothelium derived relaxing factor(EDRF). Our results suggest that an as yet unidentified arginine derivative from the endothelium may be the biological precursor of EDRF.
与精氨酸不同，L-精氨酸的苯甲酰衍生物能以浓度依赖的方式使预先收缩的大鼠主动脉环舒张。最有效的舒张剂是N-α-苯甲酰-L-精氨酸乙酯。亚甲蓝可消除这种舒张作用，但吲哚美辛不能。当与大鼠主动脉环一起孵育时，苯甲酰衍生物表现出瓜氨酸和亚硝酸根离子特有的比色反应。这表明大鼠主动脉中存在一种类似肽基精氨酸脱亚氨酶的活性。瓜氨酸没有血管舒张特性。亚氨酶反应的另一种产物是氨，它可通过加氧酶途径生成一氧化氮，即推测的内皮源性舒张因子（EDRF）。我们的结果表明，内皮中一种尚未鉴定的精氨酸衍生物可能是EDRF的生物前体。
