川芎嗪对阿霉素致大鼠膈肌损伤的保护作用

目的探讨阿霉素对大鼠膈肌的损伤机制及川芎嗪对阿霉素致大鼠膈肌损伤的保护作用.方法 SD大鼠 30只,随机分为正常对照组、模型组、川芎嗪组,每组 10只.应用离体大鼠膈肌肌条方法,分别测量其单收缩张力(Pt)、最大强直张力(Po)、张力-频率曲线(Force-frequency)、峰值收缩时间(CT)、半舒张时间(1/2RT),张力最大上升速率( dT/dtmax)及张力最大下降速率(-dT/dtmax),同时检测膈肌中超氧化物歧化酶(SOD)、丙二醛(MDA)含量.结果 1)模型组大鼠膈肌 Pt、Po、 dT/dtmax及-dT/dtmax明显低于正常对照组(P<0.01),川芎嗪组大鼠膈肌的 Pt、Po、 dT/dtmax及-dT/dtmax与正常对照组比较无显著性差异.川芎嗪组的 CT明显长于模型组及正常对照组(P<0.01).予 10、20、40、60、100Hz频率刺激膈肌时,模型组大鼠膈肌张力明显低于正常对照组及川芎嗪组. 2)与正常对照组比较,模型组大鼠膈肌组织的 SOD含量明显降低,MDA含量明显升高(P<0.01),川芎嗪组的 SOD及 MDA含量与正常对照组比较无显著性差异.结论阿霉素能使大鼠膈肌氧自由基生成增多,清除减少,收缩功能减低;川芎嗪能拮抗阿霉素所致膈肌氧自由基生成增加及清除减少,增强膈肌收缩功能,对膈肌损伤有明显的保护作用.

Protective Effect of Ligustrazine on Diaphragm Injury Induced by Doxorubicin in Rats

Objective To explore the mechanism of doxorubi cin in impairing diaphragm and to investigate the prevention of doxorubicin -induced diaphragm i njury in rats.Methods Thirty SD rats were divided into norm al control group(n=10),model group(n=10)and ligustrazine group(n=10).Diaphragm strips was isolated to ob serve peak twitch ten-sion(Pt ),maximum titanic tension(Po),force -frequency curve,time to peak contraction(CT),half relaxation time (1/2RT),maximal rates of the rise of tension(+dT /dt max )and maximal rates of the decrease of t ension(-dT /dt max ).Meanwhile,the contents of superoxide dismutase(SOD)and malondialdehyde(MDA)in the diaphragm were also mea-sured.Results1)Pt,Po,+dT /dt max and -dT /dt max in the model group were lower than those in the control group(P<0.01);the above four indexes in ligustrazine group did not differ from those in the normal control group and CT was pr o-longed as compared with that in the mo del group and in the normal control group(P<0.01);stimulated by the frequen-cy of 10,20,40,60,100Hz ,diaphragm tension in the model group was obviously decreased as compared with that in the normal control group and ligustr azine group.2)SOD content was decreased and MDA increased in the control group as compared with the normal control gro up(P<0.01);the differences of SOD and MDA were i nsignificant between control group and ligustrazine group.Conclusion Doxorubicin can depress the contraction of diaphragm and increase the pr oduc-tion of oxygen free radicals and redu ce their clearance;ligustrazine ca n protect diaphragm from damage by counteracting the above effects of doxorubicin.