Antiallergic activity of Aristolochia bracteolata Lank in animal model.

Antiallergic activity of Aristolochia bracteolata was evaluated by using compound 48/80 induced anaphylaxis, dermatitis rhinitis and pruritus, as a preclinical model for acute phase of hypersensitivity reactions. The late phase hypersensitivity was evidenced by considering toluidine diisocyanate induced volume of bronchoalveolar fluid secretion and its inhibition. The possible antiallergic mechanism was evaluated by using compound 48/80 induced mast cell activation and estimated serum nitric oxide (NO), rat peritoneal fluid NO, bronchoalveolar fluid NO and blood histamine levels. The present study implied that the chloroform extract of Aristolochia bracteolata had potent and significant inhibitory effect on compound 48/80 induced pruritus and dermatitis activity in Swiss albino mice. It showed significant effect in toluidine diisocyanate induced rhinitis in swiss albino mice. Mast cell membrane stabilization activity was also observed in compound 48/80 induced mast cell activation. A significant reduction was observed in serum nitrate levels, rat peritoneal fluid nitrate levels and BAL nitrate levels. The extract was also found to possess significant inhibitory effect on blood histamine levels. It could be concluded that chloroform extract of A. bracteata possess potent antiallergic activity, possibly through mast cell membrane stabilization, inhibiting NO and histamine pathway.