Antiasthmatic property of polyherbal preparation E-721 B

E‐721B and its aqueous extract were studied for its antiasthmatic effect in various experimental models using rats and guineapigs. E‐721B produced significant and dose‐dependent inhibition of peritoneal mast‐cell degranulation induced by compound 48/80 and egg‐albumin in sensitised rats. The inhibition was comparable to that with disodium cromoglycate, ketotifen, and prednisolone. E‐721B administered 2 h before the experiment and once daily for seven days significantly increased the preconvulsion time of acetylcholine and histamine aerosol‐induced bronchospasm. It also significantly reduced mortality in guineapigs produced by egg albumin‐induced anaphylactic shock and also reduced bronchoalveolar fluid eosinophil count in the same animals. E‐721B significantly inhibited the acetylcholine and histamine‐induced contraction of different isolated smooth muscle preparations from rats and guineapigs. Contrary to these findings E‐721B produced dose‐dependent contraction of the rat anococcygeus muscle which was blocked by prazosin. Thus our observations establish the antiasthmatic potential of this herbal formulation. Copyright © 2003 John Wiley & Sons, Ltd.