门静脉部分结扎大鼠门脉血中一氧化氮水平与高动力循环综合征的关系

Relationship Between Level of Nitric Oxide in the Blood of Portal Vein and the Hyperdynamic Circulatory Syndrome in Partial Portal Vein Ligative Rats

目的 了解一氧化氮 (NO)在高动力循环综合征 (HCS)形成中的作用以及NO水平升高或降低时对HCS的影响。方法 结扎大鼠部分门静脉使之形成稳定的HCS模型后 ,应用一氧化氮合成酶 (NOS)抑制剂NG 甲基 L 精氨酸(L NMMA)处理前、后检测其门静脉血中NO含量及肝组织NOS活性 ,同时检测左心室功能及血流动力学指标。结果 门静脉部分结扎后大鼠门静脉血中NO含量及肝组织中NOS活性二者呈平行变化 ,与HCS的形成关系密切 ;在注射L NMMA后门静脉血中NO含量及肝组织中NOS活性均明显降低并接近对照组水平 ,HCS明显缓解。结论 NO在HCS形成中起关键作用。降低或消除NO的作用则能明显缓解或阻断HCS ,使门静脉压力明显降低直至恢复到正常范围。

Objective To understand the effect of nitric oxide (NO) on the formation of hyperdynamic circulatory syndrome (HCS) and the influence of level of NO on HCS. Methods After establishment of stable HCS in partial portal vein ligated rats,the quantity of NO in blood of portal vein and the activity of nitric oxide synthase (NOS) in liver were determined by pre and post injection of inhabitor of NOS (N G methyl L arginine) and hemodynamics was supervised simultaneously.Results The quantity of NO was paralleled with the activity of NOS and was elevated markedly by 24 hours after operation and reached the top by 48 hours after surgery. These sequential changes were coincided with the dilation of general vascularture. There was a close relation between this changes and the formation of HCS.The quantity of NO and the activity of NOS were decreased significantly to the level of the control group after injection of N G methyl L arginine (L NMMA). L NMMA inhabited the activity of NOS and blocked the production of NO. HCS ameliorated obviously. Conclusion NO plays an important role in initiating the dilation of general vascularture and plays a critical role in the formation of HCS. HCS will be ameliorated obviously or be blocked completely by eliminating the effect of NO and the portal pressure will decreased significantly or recover to normal range.