A Moderate Carnitine Deficiency Exacerbates Isoproterenol-Induced Myocardial Injury in Rats

摘要: The myocardium is largely dependent upon oxidation of fatty acids for the production ATP. Cardiac contractile abnormalities and failure have been reported after acute emotional stress there evidence that catecholamines are responsible stress-induced heart injury. We hypothesized carnitine deficiency increases risk Carnitine was induced in Wistar rats by adding 20 mmol/L sodium pivalate to drinking water (P). Controls (C) received equimolar bicarbonate a third group (P + Cn) along with 40 mmol/L carnitine. After 15 days, 6 rats/group were used evaluate function isolated hearts under infusion 0.1 μM isoproterenol 20 submitted single subcutaneous administration 50 mg/kg isoproterenol. Isoproterenol C markedly increased rate, left ventricular (LV) systolic pressure coronary flow rate. In P rats, rate LV but these not paralleled rise diastolic progressively increased. Subcutaneous 15 % mortality 50 % (p < 0.05). Hearts surviving examined 15 days later appeared clearly dilated, presented marked impairment greater increase tumor necrosis factor α (TNFα) levels. All detrimental effects negligible P + Cn rats. Our study suggests exposes injury when sympathetic nerve activity greatly stimulated, example during emotional, mental or physical stress.