Effect of Kauranes from Montanoa spp on rat uterus

Abstract

The effect of kaurenoic acid (from Montanoa frutescens), grandifloric and kauradienoic acid (from M. tomentosa) and 16 alpha-hydroxy-ent-kauran-19-oic acid and its methyl ester (from M. hibiscifolia) were assayed on the contractions of rat uterus induced by acetylcholine, oxytocin and serotonin. The four kauranes assayed inhibited the contractile activity induced by the three agonists through a mechanism independent of either beta(2)-adrenergic or H-2-histaminergic receptors present in uterine smooth muscle. Oestrogenized uteri treated with kauradienoic acid underwent histological changes including epithelial flattening and desquamation. (C) 1997 by John Wiley & Sons, Ltd.