Investigation of oral selegiline and rasagiline administration on QT interval in conscious rabbits.

Rasagiline (RSG) and selegiline (SEL) are potent selective monoamine oxidase-B inhibitors and used in the treatment of Parkinson's disease. Selegiline is metabolized in vivo to I-methamphetamine and I-amphetamine which effect cardiovascular system. Therefore, the aim of this study was to evaluate and to compare the effects of long-term use of these drugs on QT interval in conscious rabbits. The study involved 17 New Zealand rabbits of both sexes, aged between 7 and 14 months. Control group (CG, n = 6) was orally given isotonic saline solution at dose of 0.5 cc/per rabbit. The SEL group (SG, n = 6) received 5 mg/per rabbit SEL orally twice daily (09:00 am and 09:00 pm) for 14 days. The RSG group (RG, n = 5) was orally given of RSG at 1 mg/per rabbit daily for 14 days. Electrocardiographic records were taken before the experiment (baseline) and at 1st, 7th, and 14th days of experiment by direct writing electrocardiograph for two groups. Heart rate (HR), QT and QTc values were determined from ECG records. HR did not significantly differ in both treatment groups through the experimental period when compared to baseline values. The significant prolongation of QT and QTc values were observed at 7th, and 14th day (p < 0.01) in SG and 1st day of experiment in RG (p < 0.05) as compared to baseline values. In conclusion, the results obtained suggest a statistically significant effect of SEL on QTc prolongation when compared to RAS. QTc prolongations should be taken into account in Parkinson's disease where autonomic system is involved.