RESUMO
This study evaluated the antispasmodic, bronchodilator and anti-platelet activities of Abies webbiana to rationalize some of its folk uses in gut and airways disorders and inflammation. The crude extract of A. webbiana (Aw.Cr) caused a complete relaxation of both spontaneous and K(+) (80 mM)-induced contractions in isolated rabbit jejunum in a concentration-dependent manner. Aw.Cr shifted the Ca(++) concentration-response curves (CRCs) to the right, in a fashion similar to verapamil, confirming its Ca(++) channel blocking (CCB) effect. In isolated rabbit tracheal preparations, it caused relaxation of carbachol (1 µM) and K(+) (80 mM)-induced contractions comparable to verapamil suggesting that the bronchodilatory effect may possibly be mediated through CCB activity. Aw.Cr was found to be the inhibitor of both ADP- and epinephrine-induced aggregation of human platelets thereby suggesting therapeutic potential in this plant against thrombo-embolic conditions. The exhibited anti-platelet effect was observed at low doses against epinephrine as compared to ADP. This study confirmed the presence of spasmolytic activity in Abies webbiana through possible blockade of Ca(++) channels providing evidence for its folkloric use in gut and respiratory disorders in addition to anti-platelet activity.
