Bronchodilating and uterine activities of Ageratum conyzoides extract

Abstract

Ageratum conyzoides root and aerial part extracts induced relaxation on isolated trachea. There was no significant difference between the activities of root and aerial part extracts. When Histamine (hist) and the plant extract were introduced into the tissue bath simultaneously, 14% of the activity of the plant extract was inhibited. When the same procedure was used, 5-hydroxytryptamine (5-HT) inhibited 21% of the plant extract activity. Conversely, 86% and 79% activities of hist and 5-HT respectively, were inhibited by the plant extract. This could be the mechanism of its activity as a tracheal relaxant. Acetylcholine (ACh) and 5-HT induced contractions on isolated rat uterus. The treatment of isolated rat uterus with the plant extract inhibited uterine contractions induced by 5-HT, suggesting that the plant extract exhibited specific antiserotonergic activity on isolated uterus. However, the uterine contraction caused by ACh was unaffected by the plant extract.