Effect of Aloe vera (Aloe barbadensis) gel extract on re-polarization state of myocardium in albino rat

Aloe vera is a well known medicinal plant contents with over 75 different ingredients, anthraquinones, saponins, and sterols. Recent studies showed that it is a potent hypolipedimic, hypoglycemic and antioxidant. In present study we investigated the dose dependent effect of aloe vera gel on repolarization state of myocardium, heart rate, QRS complex and QT interval using electrocardiograph in albino rats. A total of 24 male albino rats were divided into four groups, one control and three experimental. An aqueous solution of Aloe barbadensis was prepared by taking fresh leaf of aloe plant. Animals of all the groups were anesthetized and were treated (i.p.) with aloe vera gel extract in doses of 100, 200 and 300 mg/kg body weight in experimental groups I, II and III, respectively. Electrocardiograms were recorded at 0 (basal), 15 and 30 min after injection of aloe vera/saline. Aloe vera in doses of 200 mg increases QTc from 73.10 +/- 3.25 (mv) to 75.04 +/- 1.93 (mv) and in 300 mg, QTc increased from 72.10 +/- 1.85 to 76.10 +/- 1.56 which is statistically significant (p<0.05). Higher doses of aloe vera cause prolongation of QTc interval in albino rat. Therefore administration of aloe vera in higher doses may be cardio toxic.