Hirai Y, Morishita S, Ito C, Sakanashi M
Research Laboratories, Kyushin Pharmaceutical Co., Ltd., Tokyo, Japan.
Nihon Yakurigaku Zasshi. 1992 Aug;100(2):127-35. doi: 10.1254/fpj.100.127.
Effects of bufadienolides such as bufalin (BF) and cinobufagin (CB), the main components of Senso (Ch'an Su), on myocardial Na+,K(+)-ATPase activity, the cardiotonic activity in vivo and the action potential of isolated guinea pig papillary muscle cells were compared with those of other cardiotonic drugs. 1) The rank order of potency for inhibition of myocardial Na+,K(+)-ATPase activity was BF greater than digoxin (DG) greater than digitoxin (DT) greater than telocinobufagin greater than gamabufotalin greater than cinobufotalin greater than CB greater than g-strophanthin (GS) greater than digitoxigenin (DTG) greater than resibufogenin (RB) when compared at the 50% inhibitory concentration. 2) In isolated papillary muscle cells, CB shortened the action potential duration (APD) dose-dependently. The order of potency for shortening of APD was GS greater than CB greater than DTG much greater than DT. 3) In open-chest guinea pigs, intraduodenal administration of BF or CB increased the myocardial contractile force (MCF), but did not affect the heart rate. The order of potency for increase in MCF was as follows: methyldigoxin, proscillaridin greater than BF greater than CB greater than DG greater than Senso much greater than DT, DTG, RB. These results indicate that CB has a shortening effect on APD and an inhibitory effect on Na+,K(+)-ATPase activity along with its cardiotonic effect, like GS.
将蟾酥（Ch'an Su）的主要成分如蟾毒灵（BF）和华蟾酥毒基（CB）等蟾蜍二烯羟酸内酯对心肌钠钾ATP酶活性、体内强心活性及豚鼠离体乳头肌细胞动作电位的影响与其他强心药物进行了比较。1）在50%抑制浓度下比较时，抑制心肌钠钾ATP酶活性的效力顺序为：BF＞地高辛（DG）＞洋地黄毒苷（DT）＞远华蟾毒精＞南美蟾毒精＞华蟾酥毒基＞CB＞毒毛花苷G（GS）＞洋地黄毒苷元（DTG）＞脂蟾毒配基（RB）。2）在离体乳头肌细胞中，CB剂量依赖性地缩短动作电位时程（APD）。缩短APD的效力顺序为：GS＞CB＞DTG远大于DT。3）在开胸豚鼠中，十二指肠内给予BF或CB可增加心肌收缩力（MCF），但不影响心率。增加MCF的效力顺序如下：甲基地高辛、海葱苷元＞BF＞CB＞DG＞蟾酥远大于DT、DTG、RB。这些结果表明，CB与GS一样，在具有强心作用的同时，对APD有缩短作用，对钠钾ATP酶活性有抑制作用。
