Publication:

Effect of metformin on ECG, HR and BP of rats administered with cardiotoxic agent doxorubicin

Background Cardiovascular complications during drug therapy is worrisome and has been known to increase morbidity and mortality. The aim of this study was to investigate the effect of metformin on BP, HR, and ECG, after subacute administration of doxorubicin in rats.

Methods Laboratory acclimatised animals were divided into 4 experimental groups consisting of group I as the control, given 0.5ml normal saline. Group II, received 3mg/kg doxorubicin on alternate days, while group III was given 300mg/kg metformin. The last group of animals were treated with 300mg/kg metformin, 30 min later, the animals were injected doxorubicin ip. The treatment lasted for 15 days thereafter, ECG, HR and BP were measured with anaesthesia.

Results Result showed that doxorubicin induced ECG changes in terms of increased PR and QT intervals significantly. Whereas, QRS and RR intervals were at same time significantly decreased. Metformin was observed to significantly attenuate these changes. In addition, metformin restored decreases in HR that was caused by doxorubicin in a significant fashion. However, metformin alone produced a decrease in HR compared with control. The observed reduced SBP and DBP produced by doxorubicin were also alleviated by the administration of metformin. There were increases in BP parameters measured in normotensive rats with metformin alone.

Conclusions In conclusion, metformin was found to attenuate doxorubicin-induced alteration in ECG pattern and restored the mechanical and physiological functions of the rat heart. Our data further suggests monitoring of CVS changes such as ECG particularly with drugs known to cause myocardial injury.