| Summary: | The infusion of the desertic plant <i>Nolana ramosissima</i> I.M. Johnst showed vascular smooth muscle relaxation in rat aorta and the presence of several phenolic compounds, which were detected by high resolution UHPLC-Orbitrap-HESI-MS. In addition, five flavonoids were rapidly isolated from a methanolic extract using high-performance counter-current chromatography (HPCCC). The <i>N. ramosissima</i> extract showed endothelium-independent relaxation effect in rat aorta. Sixty-one compounds were detected in the infusion, mainly glycosylated flavonoids, flavanones and several oxylipins, suggesting that a synergistic effect between the compounds in the extracts could be responsible for the relaxation activity. Vascular activity experiments were done in isolated organ bath. In rat aorta, a nitric oxide inhibitor did not prevent the relaxation effects of the extract; however, a selective guanylyl cyclase inhibitor partially blunted this effect. The compound <b>5</b>,3′-dihydroxy-4′7-dimethoxyflavone presented higher relaxation effect than 100 μg/mL of <i>N. ramosissima</i> extract. The extract and the isolated metabolites from <i>N. ramosissima</i> can show relaxation effects on rat aorta by a mechanism that is independent of the endothelium.
|
|---|