[Asymmetric responses of epicardial and endocardial fibers of the dog atrium to cholinergic effects].
The ACh shortened the AP in canine epicardial and endocardial cells, the effect being more obvious in the latter. The findings suggest that 4-aminophyridine-sensitive transient outward current is expressed in canine atrial epicardial and endocardial cells, that the ACh exerts direct effects on epicardial and endocardial AP duration, that differential responses of epicardial and endocardial AP duration to the ACh may alter the gradient of repolarisation across the atrial wall and contribute to the vagus-indoced atrial flutter and fibrillation.
Aniukhovskiĭ
E P
EP
Cardiological Research-Industrial Complex, Moscow, Russia.
Rozenshtraukh
L V
LV
D000109:Acetylcholine / Q000494:pharmacology*; D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D016275:Atrial Function; D004285:Dogs; D004699:Endocardium / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D005260:Female; D006325:Heart Atria / Q000187:drug effects / Q000648:ultrastructure; D066298:In Vitro Techniques; D008297:Male; D018485:Muscle Fibers, Skeletal / Q000187:drug effects / Q000502:physiology*; D010496:Pericardium / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure
D000109:Acetylcholine