大剂量肾上腺素对心肺复苏后大鼠脑组织SOD、MDA的影响

目的:采用窒息致心跳骤停大鼠心肺复苏模型,通过观察应用大剂量肾上腺素和标准剂量肾上腺素复苏后脑组织超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量的变化,评价大剂量肾上腺素对复苏后脑组织氧自由基的影响。方法:75只大鼠,随机分为3组,假手术组(C组)、大剂量肾上腺素组(H组)和标准剂量肾上腺素组(S组),每组25只。采用窒息致心跳骤停,心跳骤停10min后,经主动脉注入复苏合剂。C组在动脉置管15min后,H组、S组在自主循环恢复(ROSC)后30、60、120min时点采集脑组织标本。检测脑组织SOD活性、MDA含量并进行统计分析。结果:ROSC后各个时点,S组、H组SOD活性均明显低于C组(P<0.05),且随时间延长进行性减低。两组MDA含量则随时间进行性增加,均高于C组(P<0.01)。在ROSC后60及120min时点H组SOD活性低于S组(P<0.05),而MDA含量高于S组(P<0.05)。结论:应用大剂量肾上腺素复苏后脑组织超氧化物歧化酶活性较低,丙二醛含量较高,氧自由基损伤更加严重,不利于神经功能恢复。

Effect of high-dose epinephrine on superoxide dismutase activity and malondialdehyde content in rat cerebral tissue after cardiopulmonary resuscitation

Objective:To evaluate the effect of high-dose epinephrine given during cardiopulmonary resuscitation(CPR) on cerebral injury by observing the changes of superoxide dismutase(SOD) activity and malondialdehyde(MDA) content in cerebral tissue of the rat model of asphyxial cardiac arrest.Methods:Seventy-five rats were randomly and equally divided into control group(group C),standard-dose epinephrine group(group S),and high-dose epinephrine group(group H).Cardiac arrest was induced by asphyxiation.CRP was started 10 minutes after cardiac arrest,and CRP mixture was given via aorta.The rats were killed and the cerebral tissues were sampled 30,60,and 120 minutes after the restoration of spontaneous circulation(ROSC) in groups S and H and 15 minutes after femoral artery were cannulated in group C.The activity of SOD and content of MDA in cerebral tissues were determined.Results:The activity of SOD in cerebral tissues decreased with the prolongation of ROSC and was significantly lower in groups S and H than in group C(P < 0.05).The content of MDA increased with the prolongation of ROSC and was significantly higher in groups S and H than in group C(P < 0.01).Compared with group S,the activity of SOD was lower and the content of MDA higher in group H 60 and 120 minutes after ROSC(P < 0.05).Conclusion:High-dose epinephrine decreases SOD activity and increases MDA content in cerebral tissues during CPR in rats.The cerebral injury induced by oxygen radicals is more severe in group H,which affect the recovery of neurological functions.