Cardiotoxicity induced in mice by long term ketamine and ketamine plus alcohol treatment.

Increased use of ketamine as a recreational drug in rave party has raised lots of social concerns. Although its toxicity on the central nervous system (CNS) and urinary system had been reported, its potential adverse effects on the heart is still not addressed. Using our long term ketamine addiction model in which, 1-month-old ICR mice were given ketamine intraperitoneally (i.p. 30 mg/kg) for different study periods (6 weeks, 16 weeks and 28 weeks). The electrocardiogram (ECG) and the level of troponin as well as the presence of lactate dehydrogenase were used together to determine the cardiac function of mice. ST elevations were observed in 30% of mice from 6 weeks onwards. Concomitant increase in troponin in serum and presence of lactate dehydrogenase positive cardiac cells were taken together to indicate cardiac damages. The potential interactive effects of alcohol (ethanol) and ketamine were also addressed and 0.5 ml of 10% ethanol was administrated additionally to the mice daily and orally for the last 4 weeks in the 28-week long-term ketamine treated animals. The cardiac functions of these mice deteriorated more severely as indicated by further rise in troponin levels. In addition, high number of lactate dehydrogenase positive cardiac cells and abnormal ECGs in both ketamine and ketamine plus alcohol treated models also gave coherent conclusions.