CARDIOVASCULAR EFFECTS OF AQUEOUS LEAF EXTRACT OF ARISTOLOCHIA BRACTEATA LAM. ON ISOLATED PERFUSED FROG HEART PREPARATION

ABSTRACT

Aristolochia bracteata lam. is known for many medicinal properties. The present study was undertaken to evaluate the cardiotonic activity of the aqueous extract of leaves of Aristolochia bracteata on isolated perfused frog heart preparation. The aqueous extract of Aristolochia bracteata produced positive results for alkaloids, glycosides terpenoids saponins, flavanoids, phenols, volatile oils. The aqueous extract of Aristolochia bracteata produced negative results for carbohydrates, proteins, gums and mucilage. Ringer solution without calcium was used as a vehicle for administration of aqueous extract as test and Digoxin as standard. The incremental dose of aqueous extract of Aristolochia bracteata produced positive ionotrophic and negative chronotrophic effect on isolated frog heart and is dose dependent. The test extract had not produced cardiac arrest even at a dose of 10mg/ml, a higher concentration as compared to standard, digoxin that showed cardiac arrest at dose of 0.2 mg. Hence, as compared to standard, test drug showed wide therapeutic index. The mechanism involved in the positive ionotrophic action of extract has been studied. In the trx australia  present study Theophylline increase the dose response curve of Aristolochia bracteata aqueous extract. Aristolochia bracteata aqueous extract induced positive ionotrophic effect were completely blocked by Propranolol. The data suggests that Aristolochia bracteata aqueous leaf extract induce positive ionotrophism involved any adrenergic receptor mediated action.

Key words: Cardiotonic activity, Digoxin, Calcium free Ringer’s solution, Isolated frog heart.