Nakamura T, Sakamaki T, Sato K, Ono Z, Prewitt R L
Second Department of Internal Medicine, Gunma University School of Medicine, Maebashi, Japan.
Jpn Heart J. 1994 May;35(3):363-8. doi: 10.1536/ihj.35.363.
This study investigated the effects of intravenous injection of the specific inhibitor of nitric oxide (NO) formation, NG-monomethyl-L-arginine (L-NMMA), on mean arterial pressure and regional vascular resistance in rats (n = 7). Regional vascular resistances of brain, heart, left kidney, intestine (jejunum), left testis and right testis were measured using radiolabelled microspheres before and after injection of 12.5 mg/kg of L-NMMA. Injection of L-NMMA raised mean arterial pressure significantly (p < 0.05) from 119 +/- 4 (mean +/- SEM) mmHg to 139 +/- 7 mmHg, accompanied by a significant (p < 0.05) decrease in both heart rate and cardiac index and an increase in total peripheral resistance. Regional vascular resistances in brain, heart, kidney and intestine increased significantly (p < 0.05) with L-NMMA, but no change was observed in the testes. The results indicate that the resistance of vascular beds is affected by NO synthesis, while the extent of regulation may differ among the various vascular beds.
本研究调查了静脉注射一氧化氮（NO）生成的特异性抑制剂N-甲基-L-精氨酸（L-NMMA）对大鼠（n = 7）平均动脉压和局部血管阻力的影响。在注射12.5 mg/kg的L-NMMA前后，使用放射性标记微球测量脑、心脏、左肾、肠（空肠）、左睾丸和右睾丸的局部血管阻力。注射L-NMMA后，平均动脉压从119±4（平均值±标准误）mmHg显著升高（p < 0.05）至139±7 mmHg，同时心率和心脏指数显著降低（p < 0.05），总外周阻力增加。L-NMMA使脑、心脏、肾脏和肠的局部血管阻力显著增加（p < 0.05），但睾丸未观察到变化。结果表明，血管床的阻力受NO合成的影响，而不同血管床的调节程度可能不同。
