[Effects of 2-(p-dimethylaminostyryl) pyridine methycholide (DSPM-Ci) on ECG, left atrium contractivity and on papillary muscle action potentials].
The effects of DSPM-Cl on ECG in rats, on the dose-effect curve in guinea pig left atria and on the fast action potential (AP), high-K+ depolarized slow action potential (SAP) in guinea pigs papillary muscle were examined electrophysiologically. DSPM-Cl (2 mg.kg-1) showed significant nagative frequency, negative conductivity effect, and prolonged the PP and PR interval. DSPM-CI (30-50 mumol.L-1) was shown to inhibit left atria contractility and shift the concentration-response curve of Iso and CaCl2 to the right with PD2' values of 4.60 and 4.13, respectively. In addition, DSPM-Cl was found to prolong the duration of action potential 90 (APD90) and effective refractory period (ERP), and decrease the maximal upstroke velocity (Vmax) in K(+)-depolarized guinea pigs papillary muscles. The results suggest that, like verpamil, DSPM-Cl might be a calcium antagonist.
Jiang
X Y
XY
Department of Pharmacology, Xinjiang Medical College, Urumqi.
Zhou
C M
CM
Li
D M
DM
Zhang
K J
KJ
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D003864:Depression, Chemical; D004562:Electrocardiography / Q000187:drug effects*; D004594:Electrophysiology; D005260:Female; D006168:Guinea Pigs; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects*; D010210:Papillary Muscles / Q000502:physiology*; D011726:Pyridinium Compounds / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D014700:Verapamil / Q000494:pharmacology
C107787:2-(4-dimethylaminostyryl)methylpyridine; D002121:Calcium Channel Blockers; D011726:Pyridinium Compounds; D014700:Verapamil