一氧化氮合成酶抑制剂对麻醉犬等长收缩运动的血流动力学影响

Effect of nitric oxide synthase(NOS) inhibitor on hemodynamic indexes during isometric exercise in anaesthesia dogs/

目的:比较麻醉犬等长收缩运动(IE)中注入一氧化氮合成酶(NOS)抑制剂前后心率(HR)及相关心血管指标的变化,探讨一氧化氮(NO)及NOS对IE时血流动力学变化的调节作用。方法:成年健康杂种犬14只,在安静、IE 3、6、9分钟.运动后5、10、20分钟时测定各项血液动力学指标,然后注入NOS抑制剂,重复原试验,测上述各时间点的血流动力学指标。结果:IE9分钟时HR上升明显(P<0.05),而注入NOS抑制荆后IE 9分钟时HR下降明显(P<0.05)。收缩压(SBP),舒张压(DBP)在注入NOS抑制剂后3、6、9分钟的水平均高于注入前(均为P<0.05)。在注入NOS抑制剂后心输出量(CO)变化不明显,每搏量(SV)明显上升(P<0.05)。结论:NOS抑制剂降低麻醉犬等长收缩运动时的心率,同时升高血压。如NO不被抑制,对等长收缩运动是有利的。

Objective: This experimental study observed the hemodynamic effect before and after injected nitric oxide synthase (NOS) inhibitor in anaesthesia dogs. Methods: Fourteen adult dogs performed IE by faradism stimulation. HR and hemodynamic indexes were measured during the experiment. Results: Heart rate increased at the point of IE 9 minute (P<0. 05) but decreased by injecting NOS inhibitor (P<0. 05). The level of blood pressure (BP) was higher than that before injecting NOS inhibition (P<0. 05). Cardiac output (CO) had no change. Stroke volume (SV) increased after injected NOS inhibition (P<0. 05). Conclusion: Nitric oxide synthase (NOS) inhibitor can decrease HR; simultaneously increase BP. If NOS was not inhibited, it is beneficial for isometric exercise.