title: Differential effects of trichothecenes on the canine cardiac action potential.
abstract: We investigated the hypothesis that trichothecenes directly alter cardiac electrical activity. Action potentials were recorded from electrically stimulated canine false tendons before, during and after exposure to trichothecenes (1.0 mg/l). Action potentials recorded prior to and 60 min after exposure to trichothecenes were compared statistically. T-2 toxin decreased resting potentials in interventricular septum cells (7%), decreased action potential durations in papillary muscle cells (19%) and decreased both in false tendon cells (11% and 27%, respectively). Scirpentriol shortened durations of action potentials recorded in false tendon cells (24%), but had no other effects on any of the cell types tested. T-2 tetraol shortened the duration of interventricular septum cell action potentials (35%), but had no significant effects on other cardiac cells. Adenosine-5'-triphosphate (ATP) (final concentration 1100 mg/l) reversed all the effects of the trichothecenes on canine cardiac action potentials. These action potential changes may reflect a deficit of high energy phosphate and directly contribute to trichothecene-induced arrhythmias.
mesh_terms: D000200:Action Potentials / Q000187:drug effects; D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D004285:Dogs; D004558:Electric Stimulation; D005260:Female; D006321:Heart / Q000187:drug effects*; D066298:In Vitro Techniques; D008297:Male; D009206:Myocardium / Q000166:cytology; D011690:Purkinje Fibers / Q000187:drug effects / Q000503:physiopathology; D012717:Sesquiterpenes / Q000494:pharmacology*; D013329:Structure-Activity Relationship; D014255:Trichothecenes / Q000037:antagonists & inhibitors / Q000494:pharmacology*
chemical_list: D012717:Sesquiterpenes; D014255:Trichothecenes; D000255:Adenosine Triphosphate