小剂量瑞芬太尼对感染性休克幼兔体动脉张力的影响

目的 观察小剂量瑞芬太尼(remifentanil,RF)对感染性休克幼兔体动脉血管环张力影响并探讨其机制.方法健康幼兔12只,分次制作36条幼兔离体体动脉血管环,随机分为6组:正常对照组、大肠杆菌脂多糖(lipopoly-saccharide,LPS)对照组、正常+RF组、LPS+ RF组、正常+N-硝基左旋精氨酸(L-NNA)+RF组和LPS+ L-NNA+ RF组,每组6个血管环.通过血管环张力测定,观察小剂量RF对感染性休克幼兔体动脉血管环反应性的影响,并观察预先以NO合成酶抑制剂L-NNA干预后的变化.结果正常组体动脉:与NS组比较,加入小剂量RF(4 μg/L)后各时间点(5 min、10 min、20 min)均引起体动脉明显的舒张反应,舒张幅度分别为(18.48±3.96)％、(23.63±4.42)％、(28.33±3.73)％(P＜0.05).预先以L-NNA干预后,上述舒张反应明显降低至(8.15±1.01)％、(13.08±1.46)％、(18.54±2.94)％(P＜0.05).LPS孵育后,小剂量RF(4 μg/L)对幼兔体动脉不具舒张作用,与加入NS组比较差异无统计学意义(P＞0.05),预先以L-NNA干预后,体动脉对该剂量RF张力变化差异无统计学意义(P＞0.05).结论小剂量RF对正常幼兔体动脉具有舒张作用,与NO产生有关；对LPS孵育的幼兔体动脉不具有舒张作用,对体动脉的张力调节与NO无关.

Effect of low-dose remifentanil on the systemic artery tension of baby rabbit with septic shock

Objective To investigate the effect and mechanism of low-dose remifentanil(RF)on systemic artery tension of baby rabbit with septic shock.Methods Thirty-six systemic artery strips were prepared from 12 baby rabbits and randomly divided into 6 groups:control group,lipopoly-saccharide(LPS)group,RF group,LPS + RF group,NG-nitro-L-arginine(L-NNA)pretreated group,LPS + L-NNA pretreated group.Each group had six rings(n =6).The effect of low-dose RF on the systemic artery tension of baby rabbit with septic shock was observed with isolated vascular ring technique.The change was also obversed after L-NNA pretreatment.Results In control group:the relaxant rates after low-dose RF at the time point of 5 min,10 min,20 min were(18.48±3.96)％,(23.63±4.42)％,(28.33±3.73)％(P＜0.05),compared with NS group.After pretreatment with L-NNA,RF-related relaxant rates of systemic arteries decreased significantly to(8.15 ± 1.01)％,(13.08 ± 1.46)％,(18.54 ±2.94)％(P ＜ 0.05).In LPS group,low dose RF(4 μg/L)did not bring out any response to systemic arteries(P ＞0.05).The tension was not affected with pretreatment of L-NNA(P ＞ 0.05).Conclusion These results suggest that low dose RF has relaxant effect on systemic arteries of baby rabbits,and NO may be involved.Low dose RF has no relaxant effect on LPS-pretreated systemic arteries of baby rabbits,and it has no association with NO.