新型正性肌力药物维纳利酮对离体犬心室乳头肌细胞内电位的影响

Effect of a New Positive Inotropic Agent(OPC-8212) on Intracellular Potential of Isolated Canine Ventricular Papillary Muscle

作者采用微机化的智能仪记录及处理资料,研究了我校新合成药维纳利酮(又名OPC—8212)对14例犬心肌细胞内电位的影响。结果:静息电位(RP)、动作电位振幅(APA)和0期去极最大速度(V_(max))在维纳利酮作用前后均无显著差异,而动作电位全程(APT)、动作电位复极至1/3时程(APD1/3)及复极至2/3时程(APD 2/3)均有明显增加。平台期有所抬高。提示维纳利酮并不影响心肌细胞膜静息时的K^+通透性,也不影响快Na^+通道的激活和开放数目。而有可能增加Ca^(2+)通道的开放时间、增加Ca^(2+)内流;也可能同时具有减弱延迟外向钾电流(Ik)和内向整流钾电流(Ik_1)的作用。因此维纳利酮有可能成为一种很有希望的非甙、非儿茶酚胺类的新型正性肌力药物。

Tnis Andy Med intraCellularatro-eleotrode techniO to ob8erve the effat OfOPC-8212 (Vesnarinon6on 1niracel1ular PO-tentisl Of hotaled Canine ventriCUl8r paPil-lary mWe. The record and data proces-aing were eq16ted by comPUerbed1nt6lled1te 1ndroent designed byOllme1ves.The results of intracellar sord in l4canine veniriodl8r PaP1llary muscle shOwednO slgallleaat thenge ln the resting PO-tenita1 (RP), amPlitude of atiOn poeatta1(APA) and matrim dePOlarbe velocityof 0 Pwt (Vm..). Bu ~chatly ln-oreaSed wbD1e wtton of at1On poteottal(APT). The dundiOn of rePOl8rhatiOnto 1/3 (APD 1 /a) and to 2/3 (APD2/8)steniftoantly increased too. The plateauptw rais6d. These results suggeSt thatK+ permeab1llty at reSt1ng myMrdiac cel1membrane may the nOt been effeCted byOPC--a212. ACt1Vatw Of the fast sodiilmcwte1 may have nO been effected tOO.The reanlts of our Andle8 also SUgge thattwtd flOw of Ca'+ inOMd. Th6delayed ootward K+ (Ik) and th9 inwardredfwt K+ current (Ik, ) POssible de-creased. ThUs, the OPC-8212 mgh become aWtwside and boeOhOlamine newpebo thetrOPic drUg.