This study evaluates the effects on arterial pressure and pithed heart frequency rate induced by the ethanolic extract of Solanum tuberosum, a species used in Colombian folk medicine for the treatment or arterial hypertension, compared with a-solanine and a-chaconine -the main glycoalcaloids of S. tuberosum- the mixture of both glycoalcaloids (50:50) and chlorogenic acid, the main polyphenolic compound present in this species. The effect of the extract in presence of noradrenalin (0.25 - 2.5 μg/Kg, IV) and L-NAME (10 mg/Kg, IV), inhibitor of nitric oxide sintase, is also studied. These results show that whereas the etanolic extract decreases the blood pressure in a dose - response manner (1 μg/Kg - 10 mg/Kg, IV) and reduces the increase of this variable induced by noradrenalin. It has been not demonstrated that the glycoalcaloid compounds, the alkaloidal mixture (50:50), or the chlorogenic acid were able to reduce the arterial pressure. The effect of the extract is reverted partially in the presence of L-NAME. In conclusion, the etanolic extract of S. tuberosum exerts hypotensive effects related partially with the nitric oxide production, non-attributable to the presence of a-solanine, a-chaconine or chlorogenic acid.