摘要
目的:观察银杏叶提取物银杏酮酯(GBE50)抗模型动物心律失常的药效并研究其机制。方法:采用乌头碱(Aco)、哇巴因(Oua)制作大鼠整体心律失常模型,体表心电记录;哇巴因和高钙诱发豚鼠右心室乳头肌迟后除极和触发活动,细胞内微电极记录。观察银杏酮酯对上述心律失常模型的影响。结果:8,16 mg.kg-1GBE50iv提高了哇巴因诱发室性早搏(VP)的阈剂量;16 mg.kg-1GBE50提高了哇巴因诱发室性心动过速(VT)的阈剂量(P<0.05,P<0.01)。GBE50能够提高乌头碱致心律失常的阈剂量:其中8 mg.kg-1GBE50iv能够提高乌头碱诱发VT的阈剂量,16 mg.kg-1GBE50iv能够提高乌头碱诱发的室性纤颤(VF)、心脏停搏(CA)的阈剂量,32 mg.kg-1GBE50iv能够提高乌头碱诱发VP,VT的阈剂量(P<0.05,P<0.01)。银杏酮酯可以明显抑制哇巴因、高钙诱发的延迟后除极(DAD)和触发活动(TA),并呈一定的浓度依赖性。GBE50高、中、低各剂量组的DAD潜伏期的延长、DAD的幅值和时程及DAD下方的面积与对照组比均存在明显差别(P<0.01);TA发生率与对照组相比减少。结论:银杏酮酯增加了Aco,Oua造成的大鼠VP,VT,VF,CA的诱发剂量,且作用呈一定浓度依赖性。银杏酮酯延长了DAD的潜伏期,缩短了DAD的时程,减少了DAD的幅值,抑制了TA的发生,表明了银杏酮酯有抗心律失常作用,这一作用与抑制心律失常时异常的电活动过程有关。
Objective： The action and mechanism of ginkgo leaf extract （EGB 50）in fighting arrhythmia were studies. Method： The animal model of arrhythmia was established by intravenous drip of aconitine and ouabain, and the standard microelectrode technique were used. Result： In Oua model,threshold doses of ouabain induced VP,VT,VF,CA were observed.GBE50 significantly increased threshold doses of ouabain.In Aco model, threshold doses of Aco induced VP, VT, VF, CA were observed, GBE50 significantly increased threshold doses of Aco. Effects of GBE50 on delayed afterdepolarization and triggered activity induced by ouabain in guinea pig papillary muscles DADs and TA were markedly inhibited by GBE50. The amplitude and duration of DADs were reduced by GBE50 （50 mg·L^-1） from （13.25±2.38）mV and （198.38±53.62） ms to （4.04±1.44） mV and （57.00±18.62） ms, respectively, and the induced time of DADs was prolonged from （12.37±2.26） to （23.00±4.00） min. TA was reduced from 87.5% to 16.67%（P〈0.05～0.01）. GBE50 （2,10 mmol·L^-1） had significant therapeutic effects on DADs. The amplitude and duration of DADs were reduced to （10.41±3.06） mV, （8.92±2.68） mV and （128.33±18.91） ms, 103.33 20.64 ms（P〈0.05～0.01 vs control）.Conclusion： GBE50 can fight arrhythmia following aconitine and ouabain.GBE50 have inhibitory effects on DADs and TA induced by ouabain and high Ca^2＋ in guinea pig papillary muscles.
出处
《中国中药杂志》
CAS
CSCD
北大核心
2010年第2期199-203,共5页
China Journal of Chinese Materia Medica
基金
上海市教委重点学科项目(J50301)
