Isolated paced guinea pig left atrium: a new ouabain-induced arrhythmia model.
Ouabain (1.0 x 10(-6) M) produced a uniform, consistent and reproducible arrhythmia on paced guinea pig left atrium bathed in Ringer-Locke solution. A second spell of arrhythmia of similar intensity and pattern, which had the same latency to onset, was reproduced 60 min after the first spell of arrhythmia. Lignocaine (3.46 x 10(-5) M) and propranolol (1.69 x 10(-5) M) gave full protection against the second spell of arrhythmia, whereas lower doses of these drugs were able to delay the onset and reduce the duration. Clonidine (3.75 x 10(-5) M), however, was found to be ineffective. This model can be used for the detection and assessment of directly acting antiarrhythmics in very low concentrations, since this is a sensitive and reliable method.
Thomas
G P
GP
Department of Pharmacology, I.D.P.L. Research Centre, Hyderabad, India.
Varma
R K
RK
D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000494:pharmacology; D001145:Arrhythmias, Cardiac / Q000139:chemically induced* / Q000188:drug therapy / Q000503:physiopathology; D016279:Atrial Function, Left / Q000187:drug effects / Q000502:physiology*; D003000:Clonidine / Q000494:pharmacology; D004195:Disease Models, Animal; D004341:Drug Evaluation / Q000379:methods; D005260:Female; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008012:Lidocaine / Q000494:pharmacology; D008297:Male; D010042:Ouabain; D011433:Propranolol / Q000494:pharmacology; D015203:Reproducibility of Results
D000889:Anti-Arrhythmia Agents; D010042:Ouabain; D008012:Lidocaine; D011433:Propranolol; D003000:Clonidine