Electropharmacological actions of the constituents of Sinomeni Caulis et Rhizome and Mokuboi-to in guinea pig heart.
Cardiac actions of the constituents of Sinomeni Caulis et Rhizome (SCR) and Mokuboi-to, a traditional herbal drug, were investigated. In voltage-clamp experiments, sinomenine (1 mM) and tetrandrine (100 microM) inhibited the ionic currents concentration-dependently. The constituents affected the action potential configurations. In multicellular preparations, SCR (1 mg/ml) decreased the maximum rate of depolarization. Tetrandrine (30 microM) and sinomenine (300 microM) also had similar effects, but magnoflorine (1 mM) had less or no effect. Dysrhythmias were abolished under Ca(2+) overload conditions by sinomenine. These results indicate that at even acute administrations, these drugs exert the active electropharmacological actions and cardioprotections.
Satoh
Hiroyasu
H
Department of Pharmacology, Division of Oriental Medicine, Nara Medical University, School of Medicine, Kashihara, Nara 634-8521, Japan. hysat@naramed-u.ac.jp
D000200:Action Potentials / Q000187:drug effects* / Q000502:physiology; D000470:Alkaloids / Q000494:pharmacology*; D000818:Animals; D001060:Aporphines / Q000494:pharmacology*; D044182:Benzylisoquinolines / Q000494:pharmacology*; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D004365:Drugs, Chinese Herbal / Q000494:pharmacology; D006168:Guinea Pigs; D006321:Heart / Q000187:drug effects*; D007473:Ion Channels / Q000187:drug effects; D009019:Morphinans / Q000494:pharmacology*; D010210:Papillary Muscles / Q000187:drug effects / Q000502:physiology
D000470:Alkaloids; D001060:Aporphines; D044182:Benzylisoquinolines; D002121:Calcium Channel Blockers; D004365:Drugs, Chinese Herbal; D007473:Ion Channels; D009019:Morphinans; C009438:tetrandrine; C009271:sinomenine; C001670:magnoflorine