Dubois-Randé J L, Zelinsky R, Chabrier P E, Castaigne A, Geschwind H, Adnot S
Departement de Cardiologie et de Physiologie, INSERM U2, Hôpital Henri Mondor, Creteil, France.
J Cardiovasc Pharmacol. 1992;20 Suppl 12:S211-3. doi: 10.1097/00005344-199204002-00060.
To assess the ability of L-arginine to improve endothelium-dependent vasodilation in atheromatous coronary arteries, we determined whether intracoronary infusion of L-arginine could improve coronary vascular reactivity to acetylcholine (ACh) examining both conductance and resistance vessels. Coronary blood flow velocity was assessed by positioning a 3 Fr Doppler catheter into the proximal coronary artery segment (six left anterior descending and one circumflex coronary artery). Computed quantitative angiography allowed the measurement of distal diameters. After baseline measurements, ACh was infused at incremental infusion rates through the Doppler lumen catheter (3 min period each) to obtain the estimated concentrations of 5 x 10(-7), 10(-6), and 5 x 10(-6) M. After returning to baseline, L-arginine was infused at the rate of 25 mg/min (10(-3) M) through the Doppler lumen catheter. Infusion of ACh was then repeated according to the same protocol than in the absence of L-arginine. The heart rate and mean arterial blood pressure did not change at any step of the protocol. Infusion of ACh induced dose-dependent vasoconstriction of coronary distal segments with a reduction in coronary distal segments by 39 +/- 15% at 5 x 10(-6) M (p < 0.01). During infusion of L-arginine, the coronary diameter was reduced by only 16 +/- 10% (p < 0.05) at the highest ACh dose. The coronary blood flow velocity increased by 100 +/- 15% at 5 x 10(-7) M ACh (p < 0.05) but only to 16 +/- 15% at 5 x 10(-6) M ACh (NS).(ABSTRACT TRUNCATED AT 250 WORDS)
为评估L-精氨酸改善动脉粥样硬化冠状动脉内皮依赖性血管舒张的能力，我们通过检测传导血管和阻力血管，确定冠状动脉内输注L-精氨酸是否能改善冠状动脉对乙酰胆碱（ACh）的血管反应性。将一根3F多普勒导管置于冠状动脉近端节段（6支左前降支和1支回旋支冠状动脉）来评估冠状动脉血流速度。计算机定量血管造影可测量远端血管直径。在进行基线测量后，通过多普勒腔导管以递增的输注速率输注ACh（每次3分钟），以获得估计浓度为5×10⁻⁷、10⁻⁶和5×10⁻⁶M的ACh。回到基线后，通过多普勒腔导管以25mg/min（10⁻³M）的速率输注L-精氨酸。然后按照与未输注L-精氨酸时相同的方案重复输注ACh。在该方案的任何步骤中，心率和平均动脉血压均未改变。输注ACh可引起冠状动脉远端节段剂量依赖性血管收缩，在5×10⁻⁶M时冠状动脉远端节段减少39±15%（p<0.01）。在输注L-精氨酸期间，在最高ACh剂量下冠状动脉直径仅减少16±10%（p<0.05）。在5×10⁻⁷M ACh时冠状动脉血流速度增加100±15%（p<0.05），但在5×10⁻⁶M ACh时仅增加到16±15%（无统计学意义）。（摘要截短至250字）
