不同幅度脉冲膈肌起搏对兔膈肌SOD、MDA、总抗氧化能力的影响

The effect of various pulse amplitudes on the amount of SOD,MDA, and T-AOC in the diaphragm of rabbit after diaphragm pacing

目的 探讨不同幅度脉冲膈肌起搏 (diaphragmpacing ,DP)对新西兰大白兔膈肌的影响。方法 建立兔颈部DP模型 ,测定无起搏 (A)组及脉冲幅度匀速增加 (B)组、恒定 (C)组、匀速减小 (D)组起搏后膈肌组织SOD、MDA及T AOC。结果 ①DP后 ,B组较A组MDA含量增加 ,SOD及T AOC减小 (P >0 .0 5 ) ;②DP后 ,C组及D组较A组MDA含量增加 ,SOD及T AOC减小 (P <0 .0 5 ) ;③DP后 ,B组较C及D组MDA含量少 ,SOD及T AOC活力强 (P <0 .0 5 )。结论 ①脉冲幅度匀速增加通过减少氧自由基的产生 ,抗氧化能力的干扰 ,可能减缓了膈肌疲劳 (diaphragmfailure ,DF)的发生 ,②脉冲幅度匀速增加与脉冲幅度恒定和匀速减小相比 ,是一种更为合理的DP方式。

Objective To explore the effect of various pulse amplitudes on the amount of MDA, SOD and the total anti oxidation capacity (T AOC) in the diaphragm of Zelanian rabbit after diaphragm pacing. Methods Twenty four rabbits were used for establishing the diaphragm pacing model and then divided into groups A, B, C and D. No diaphragm pacing (DP) was administered with group A, while pacing with gradual increasing, gradual decreasing and constant pulse amplitude were administered, respectively, in groups B, C and D. The concentration of MDA, the activity of SOD and T AOC were examined. Results Two hours of DP with gradual increasing pulse amplitude caused increase of the amount of MDA and decrease of SOD and T AOC as compared with those without DP ( P >0.05). Two hours of DP with both gradual decreasing and constant pulse amplitude caused increase of MDA and decrease of SOD and T AOC ( P <0.05) as compared with those without DP. DP with gradual decreasing or constant pulse amplitude exerted a significantly larger effect as regard to the increase of MDA and decrease of SOD and T AOC ( P <0.05) than with the gradual decreasing pulse amplitude. Conclusion DP with gradual increasing pulse amplitude might be able to decrease the incidence of diaphragm failure (DF) through decreasing oxygen derived free radicals and maintain the anti oxidation capability.