Gonadal @entity230 are thought to be important determinants of gender-related differences in electrophysiology, such as the longer rate-corrected QTc intervals in @entity1 and the incidences of some clinical @entity943 . We studied the chronic effects of gonadal @entity230 on cardiac action potentials (APs) using standard electrophysiological techniques. Papillary muscles were removed from the hearts of oophorectomized @entity95 that had been treated with placebo, @entity53 or @entity586 ( @entity587 ). The electrocardiograms of the three groups did not differ. @entity121 were studied during drive at cycle lengths of 330 to 5000 msec. The APD30 of the @entity587 group was significantly shorter than that of the others at cycle lengths of >500 msec. The APD90 of the @entity53 group was significantly longer than that of the @entity587 group at cycle lengths of >1000 msec. The APD90 of the placebo group tended to be intermediate. The effects of the antiarrhythmic drug @entity9690 (10(-8)-10(-6) M) also were examined. @entity9690 -induced prolongation of APD90 and magnitude of early afterdepolarizations was significantly greater in the @entity53 -treated than the @entity587 -treated and placebo groups. In conclusion, in @entity95 heart, gonadal @entity230 are important determinants of base-line electrophysiological properties and the proarrhythmic response to @entity9690 .

Effects of gonadal @entity230 on ventricular repolarization and on the response to XXXX .

@entity1 :: ('9606', 'Species') :: ['women'] @entity586 :: ('MESH:D013196', 'Chemical') :: ['dihydrotestosterone'] @entity95 :: ('9986', 'Species') :: ['rabbits', 'rabbit'] @entity53 :: ('MESH:D004958', 'Chemical') :: ['estradiol'] @entity9690 :: ('MESH:C063968', 'Chemical') :: ['E4031'] @entity230 :: ('MESH:D013256', 'Chemical') :: ['steroids'] @entity587 :: ('CHEBI:16330', 'Chemical') :: ['DHT'] @entity943 :: ('MESH:D001145', 'Disease') :: ['arrhythmias'] @entity121 :: ('MESH:D009135', 'Disease') :: ['Papillary muscle APs']
@entity9690 :: (MESH:C063968,Chemical) :: ['E4031']
