摘要
呋喃二氢吡啶I(FDP I)呈浓度依赖性地抑制豚鼠心肌收缩力,IC_(50)为1.62μmol·L^1,并能抑制心肌静息后增强效应.成对刺激及正阶梯现象的收缩幅度,离体心乳头状肌细胞跨膜电位实验表明:FDPI 1.0、4.0μmol·L^1能缩短动作电位之APD_(30)·APD_(50),APD_(90),硝苯碇(Nif)0.1.1.0,4.0μmol·L^1亦能缩短APD,但两药在所试浓度范围内,对APA和V_(max)均无明显影响。
The effects of furyl-dihydropyridine I(FDP I)on the contractile response of electrically paced guinea pig heart muscles in vitro were studied.FDP I and nifedipine(Nif)produced concentration-dependent negative inotropic action in guinea pig papillary muscles; the IC50 was 1.62 and 0.42μmol·L-1,respectively.FDP 12.0μmol·L-1 decreased the post-rest contraction and developed tention evoked by paired stimulation in the left atrium.The drug also had a frequency-dependent negative inotropic effect.Action potential was investigated with a glass microelectrode in guinea pig papillary muscles and itwas found that FDP I 1.0 and 4.0μmol·L-1 brought about the decrease of APD30,APD50 and APD90 but it had no effect on action potential amplitude and Vmax.It is concluded that the negative inotropic effect of FDP I results not only from the reduction of calcium influx through the cell membrane,but also from the inhibition of calcium translocation in the sarcoplasmic reticulum.
出处
《中国药理学与毒理学杂志》
CAS
CSCD
北大核心
1993年第1期30-33,共4页
Chinese Journal of Pharmacology and Toxicology
关键词
呋喃二氢吡啶
心肌收缩
动作电位
Furyl-dihydropyridine I Nife-dipine Myocardial contraction Action potential
