EVALUATION OF THE RELAXANT ACTIVITY OF SOME UNITED-ARAB-EMIRATES PLANTS ON INTESTINAL SMOOTH-MUSCLE

Although medicinal plants are used as antispasmodic agents in folk med icine there have been no scientific studies of the phytochemical compo sition and usefulness of these plants for such treatment. Extracts of 23 plants used in the traditional medicine of the United Arab Emirates were tested for their effects on intestinal smooth muscle activity. M ost of the plants tested caused stimulation followed by inhibition of the motility of the rabbit jejunum and guinea-pig ileum. The inhibitor y effect of plants that had EC50 values < 1 mg was confirmed in-vivo u sing the gastrointestinal transit time test. These plants were phytoch emically screened for their secondary constituents. The effect of Rhaz ya stricta was investigated, particularly in relation to acetylcholine effect. The results indicated the potential of some of the plants, es pecially Rhazya stricta, as a source of antispasmodic agents.