Antihistaminic and anticholinergic activity of barberry fruit (Berberis vulgaris) in the guinea-pig ileum

Barberry (Berberis vulgaris) is a well known medicinal plant in Iran and has also been used as food. The antihistaminic and anticholinergic activity of aqueous extract of barberry fruits were investigated on isolated guinea-pig ileum, and dose response curves of histamine and acetylcholine with and without extract were plotted. The pA2 values for antihistaminic activity of extract and dexchlorpheniramine were calculated (extract; pA2 +/- S.E.M. = 4.50 +/- 0.01[-log C (g/l)]; dexchlorpheniramine; pA2 +/- S.E.M. = 9.36 +/- 0.14[-log C (M)]) and compared with each other. The pA2 values for anticholinergic activity of extract and atropine were also calculated (extract, pA2 +/- S.E.M. = 4.37 +/- 0.03[-log C (g/l)]; atropine, pA2 +/- S.E.M. = 8.99 +/- 0.13[-log C (M)]) and compared. The results indicated antihistaminic and anticholinergic activity of extract that seems to be of the competitive type.