RT Journal Article
SR Electronic
T1 A bradycardic agent, UL-FS 49, increases atrial force and decreases ventricular force in isolated, perfused heart preparations of dogs.
JF Journal of Pharmacology and Experimental Therapeutics
JO J Pharmacol Exp Ther
FD American Society for Pharmacology and Experimental Therapeutics
SP 801
OP 806
VO 265
IS 2
A1 Y Furukawa
A1 S Takayama
A1 S Sawaki
A1 Y Inoue
A1 S Chiba
YR 1993
UL http://jpet.aspetjournals.org/content/265/2/801.abstract
AB We investigated the effects of a bradycardic agent, UL-FS 49 (1,3,4,5-tetrahydro-7,8-dimethoxy-3[3-[[2-(3,4-dimethoxyphenyl) ethyl]methylimino]propyl]-2H-3-benzazepin-2-on hydrochloride), on the sinus rate and atrial contractile force and the ventricular force in the isolated, blood-perfused right atrial and left ventricular preparations of the dog and the inhibition by UL-FS 49 of the negative cardiac responses to acetylcholine, adenosine and cromakalim. UL-FS 49 (0.003-3 mumol) decreased sinus rate, increased atrial force and decreased ventricular force in a dose-dependent manner. The threshold doses of UL-FS 49 (0.03 mumol) for atrial responses were smaller than that (1 mumol) for a ventricular response. The duration of bradycardia induced by UL-FS 49 was longer than the intropic one. Propranolol and atropine did not block the positive inotropic and negative chronotropic responses to UL-FS 49, respectively, in isolated atria. UL-FS 49 (0.1-3 mumol) dose-dependently inhibited the negative chronotropic and inotropic responses to parasympathetic nerve stimulation and acetylcholine exogenously administered. UL-FS 49 at higher doses (1 and 3 mumol) attenuated the negative inotropic but not chronotropic responses to adenosine and cromakalim.(ABSTRACT TRUNCATED AT 250 WORDS)