Antispasmodic activity of an extract from Plantago lanceolata L. and some isolated compounds.

An ethanolic spissum extract of the aerial parts of Plantago lanceolata L. was examined for antispasmodic activity on isolated ileum and trachea of the guinea-pig. Isolated constituents were investigated as well. The P. lanceolata extract inhibited the contractions of the guinea-pig ileum that were induced by various agonists such as acetylcholine (ACh), histamine, potassium and barium ions. Additionally the trachea contractions induced by barium ions were inhibited. The compounds luteolin, acteoside, plantamajoside an catalpol peracetate but not catalpol, isoacteoside, lavandulifolioside and aucubin inhibited the ACh-induced contractions of the guinea-pig ileum. Luteolin and acteoside reduced the barium-induced contractions of the guinea-pig trachea. Two recently isolated compounds did not show antispasmodic activity: luteolin-3',7-diglucuronide and beta-hydroxy-acteoside.