In vitro binding receptors study by Valeriana adscendens, Iresine herbstii and Brugmansia arborea extracts.

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-HT(1A), 5-HT(2A), 5-HT(2C) serotononergic, D(1) and D(2) dopaminergic, alpha (1) and alpha (2) adrenergic receptors by radioligand assays. The results show weak affinity to 5-HT(1A) only for the aqueous extract of V. adscendens and no affinity for 5-HT(2A), 5-HT(2C) serotononergic receptors, alpha (1) and alpha(2) adrenergic receptors and D(2) receptors. As it regards D(1) receptors, only for the methanolic extract the IC(50) value was determinable. The data obtained for I. herbstii extracts have shown a low affinity for the 5-HT(1A) receptor (22.44%) and no affinity for 5-HT(2A) receptor. Otherwise these extracts showed affinity for 5-HT(2C) receptor but only for the methanolic extract the IC(50) value (inhibitory concentration 50%) was: 34.8 microg/ml. The B. arborea aqueous extract displayed weak affinity for all receptors tested, the highest levels of inhibition at the maximum concentration tested (125 microg/ml) were 38% for the 5-HT(1A), 16% for the 5-HT(2A) and 39% for the 5-HT(2C) 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.