Effects of quinidine on calcium transport activities of the rabbit heart mitochondria and sarcotubular vesicles.

摘要: Abstract The effects of quinidine on the calcium-transporting properties sarcotubular (heavy microsomal) and mitochondrial fractions rabbit heart were investigated compared with those procaine amide lidocaine. High concentrations (10 −4 -10 −3 M) markedly decreased microsomal calcium uptake; these inhibitory actions observed at all ATP but not when low Mg 2+ used in incubation medium. Calcium binding by fraction, unlike was also high quinidine. Procainc had no effect or uptake whereas lidocaine showed a stimulatory action only initial intervals incubation. ATPase activities both inhibited Quinidine, found to release about 15% bound microsomes mitochondria. results presented this study suggest that impairs transport; however, other antiarrhythmic agents such as lidocaine, which depress myocardial contractility, do decrease transport subcellular particles.