Objective: 

Adenosine has been commonly used in the treatment of supraventricular tachycardia in humans.Otherwise adenosine is a hypotensive agent that usually induces bradycardia, even cardiac arrest after coronary artery ligation. Hypotensive and bradycardic effects of adenosine make its usage unsafe in the treatment of arrhythmia. In this study, it has been aimed to research the effect of adenosine and atropine combination on the heart rate, blood pressure and on the arrhythmia induced by acute coronary artery occlusion in rats.

Methods: 

Twenty male Sprague Dawley rats were used in this study. Myocardial ischemia was produced by ligation of left coronary artery for 6 minutes and reperfusion by the releasing of this artery for 15 minutes. A1 Adenosine receptor agonist (2 Chloro - N6 – Cyclopentyl-adenosine, CCPA) 5 mg/kg/100ul and atropine in 1mg/kg /1ml intravenously at 2 min. of ligation were given alone or in combination. The arrhythmia score using the incidence and the duration of all type of arrhythmia were determined from recorded ECG

Results: 

Adenosine increased the incidence of bradycardia P<0.05. Bradycardic effect of adenosine disappeared when adenosine combined with atropine. Although the arrhythmia score was not different among groups, the incidence of ventricular tachycardia decreased in atropine and combination group in respect to control. The arrhythmic period in atropine and combination group was also longer than the control group, P < 0, 01

Conclusions: 

Bradycardic effect of adenosine was abolished by atropine. Adenosine and atropine combination was found to be effective to decrease the incidence of ventricular tachycardia. The usage of adenosine with atropine in the treatment of supraventricular tachycardia may be safer than the usage of adenosine alone.