ETHANOL INTAKE, PLASMA-CATECHOLAMINE LEVELS, AND ST-SEGMENT CHANGES WITHOUT MYOCARDIAL INJURY IN RATS WITH SHORT-TERM ETHANOL-CONSUMPTION

The authors studied the effect of short-term ethanol consumption on th e ST-segment and the association between ST-segment changes and the am ount of daily ethanol intake and levels of plasma catecholamines. The study used 63 rats (control group n = 20, study group n = 43). The rat s in the study group were exposed for 6 days to progressively larger d oses of ethanol followed by 15 days of continuous exposure to ethanol. At baseline an electrocardiogram (ECG) was recorded, and on day 25 th e ECG was repeated and plasma catecholamine levels were measured. The animals' hearts were removed and processed for histologic study. Repol arization abnormalities were observed in 68% of the ethanol-consuming rats. Two factors differentiated the subgroup of ethanol-consuming rat s with ST-segment changes from the subgroup without ST-segment changes : amount of daily ethanol intake (0.0077 +/- 0.02 ml/g/d vs 0.0058 +/- 0.019 mL/g/d) and plasma epinephrine levels (3,881 +/- 733 pg/mL vs 1 ,478 +/- 406 pg/mL). No myocardial damage was detected. Our results su ggest that in ethanol-consuming rats, high-volume daily ethanol intake and increased plasma catecholamines may mediate changes in the ST-seg ment.