Vasorelaxant effects of methyl brevifolincarboxylate from the leaves of Phyllanthus niruri.
Methyl brevifolincarboxylate (1) isolated from the leaves of Phyllanthus niruri L. showed a vasorelaxant effect on rat aortic rings. Compound 1 exhibited slow relaxation activity against norepinephrine (NE)-induced contractions of rat aorta with or without endothelium. The compound did not affect contractions induced by a high concentration (60 mM) of K+, whereas it inhibited NE-induced vasocontraction in the presence of nicardipine. These results suggest that the inhibition of NE-induced vasocontraction by compound 1 is in part attributable to a decrease in [Ca2+]i through receptor-operated Ca2+ channels.
Iizuka
Toru
T
Faculty of Pharmaceutical Sciences, Hoshi University, Tokyo, Japan. iizuka@hoshi.ac.jp
Moriyama
Hiroyoshi
H
Nagai
Masahiro
M
D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects; D001578:Benzopyrans / Q000302:isolation & purification* / Q000494:pharmacology*; D002121:Calcium Channel Blockers / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D009529:Nicardipine / Q000494:pharmacology; D009638:Norepinephrine / Q000494:pharmacology; D029803:Phyllanthus / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry; D051381:Rats; D017208:Rats, Wistar; D014662:Vasoconstrictor Agents / Q000494:pharmacology; D014665:Vasodilator Agents
D001578:Benzopyrans; D002121:Calcium Channel Blockers; D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; C087786:methyl brevifolincarboxylate; D009529:Nicardipine; D009638:Norepinephrine