Abstract
In this work we examined the affinity and the selectivity of V. adscendens, Iresine herbstii Hook. (Amaranthaceae) and Brugmansia arborea (L.) Lagerheim (Solanaceae) towards 5-HT1A, 5-HT2A, 5-HT2C serotononergic, D1 and D2 dopaminergic, α1 and α2 adrenergic receptors by radioligand assays. The results show weak affinity to 5-HT1A only for the aqueous extract of V. adscendens and no affinity for 5-HT2A, 5- HT2C serotononergic receptors, α1 and α2 adrenergic receptors and D2 receptors. As it regards D1 receptors, only for the methanolic extract the IC50 value was determinable. The data obtained for I. herbstii extracts have shown a low affinity for the 5-HT1A receptor (22.44%) and no affinity for 5- HT2A receptor. Otherwise these extracts showed affinity for 5-HT2C receptor but only for the methanolic extract the IC50 value (inhibitory concentration 50%) was: 34.8 μg/ml. The B. arborea aqueous extract displayed weak affinity for all receptors tested, the highest levels of inhibition at the maximum concentration tested (125 μg/ml) were 38% for the 5-HT1A , 16% for the 5-HT2A and 39% for the 5-HT2C receptor.The results of our experiments indicate that V. adscendens, Iresine herbstii and Brugmansia arborea were able to interact with the central 5-HT receptors thus confirming their ritual use.
Keywords: Valeriana adscendens, Brugmansia arborea, Iresine herbstii, binding, central nervous system, psychotropic agents, ethnopharmacology, receptors