title: Blocking effect of 1389-S on the sodium current in isolated guinea-pig ventricular myocytes.
abstract: Under whole cell patch conditions, 1389-S blocked the INa in guinea-pig ventricular myocytes under steady state conditions (Kdrest = 30 microM, Kdi = 2.4 microM) with a shift of the inactivation curve to the hyperpolarizing direction. Both brief and long conditioning pulses could produce a use-dependent block of 1389-S. These results suggest that 1389-S had a higher affinity to the inactivated than to the rested state under steady state conditions and had a higher affinity to the activated state during train pulses as well as to the inactivated state, making channels unavailable for conduction upon activation.
authors.affiliation: 1st Department of Internal Medicine, Tottori University School of Medicine, Yonago, Japan.
authors.forename: I
authors.initials: I
authors.lastname: Hisatome
authors.forename: S
authors.initials: S
authors.lastname: Matsuoka
authors.forename: J
authors.initials: J
authors.lastname: Miyamoto
authors.forename: M
authors.initials: M
authors.lastname: Sawaguchi
authors.forename: H
authors.initials: H
authors.lastname: Omodani
authors.forename: S
authors.initials: S
authors.lastname: Osaki
authors.forename: H
authors.initials: H
authors.lastname: Kotake
authors.forename: H
authors.initials: H
authors.lastname: Mashiba
authors.forename: R
authors.initials: R
authors.lastname: Sato
mesh_terms: D000818:Animals; D004558:Electric Stimulation; D006168:Guinea Pigs; D006321:Heart / Q000187:drug effects / Q000502:physiology; D066298:In Vitro Techniques; D009206:Myocardium / Q000166:cytology / Q000378:metabolism*; D011412:Propanolamines / Q000494:pharmacology*; D015222:Sodium Channels / Q000187:drug effects*
chemical_list: D011412:Propanolamines; D015222:Sodium Channels; C044492:711389-S