title: Negative chronotropic effect of chronic ethanol ingestion in the rat.
abstract: The chronic consumption of ethanol has been correlated with the development of arrhythmias. This study looked at the effect of chronic ethanol ingestion on the action potential of sino-atrial cells. The studies were carried out on hearts excised from male Long-Evans hooded rats, pair-fed on ethanol (E) or control (C) liquid diet. The ethanol diet supplied 35-39% of calories as ethanol. The studies of isolated sino-atrial tissue were carried out after 18-20 weeks, 30-32 weeks and 40-42 weeks on the diet. Sino-atrial cells from E and C rats were compared for changes in spontaneous rate, action potential amplitude, time to repolarize to -70 mV, and resting membrane potential. At 18-20, 30-32 and 40-42 weeks the spontaneous rate of firing of the sinus node was significantly lower in the E group as was the maximum response to isoproterenol. The time to repolarize to -70 mV was longer in E. The endogenous level of catecholamines was also lower in the E group.
mesh_terms: D000200:Action Potentials; D000437:Alcoholism / Q000503:physiopathology*; D000818:Animals; D002217:Carbachol; D006339:Heart Rate; D006801:Humans; D007545:Isoproterenol; D008297:Male; D008564:Membrane Potentials; D051381:Rats; D012849:Sinoatrial Node / Q000503:physiopathology
chemical_list: D002217:Carbachol; D007545:Isoproterenol