title: Inhibition of angiotesin-converting enzyme by quercetin alters the vascular response to brandykinin and angiotensin I.
abstract: Quercetin, one of the most widely distributed flavonoids in the plant kingdom, inhibits various enzymes. This study examined its inhibitory effect on the angiotensin-converting enzyme activity through the cardiovascular response to bradykinin and angiotensin I. Quercetin pre-treatment (88.7 micromol/kg p.o., 45 min; 14.7 micromol/kg i.v., 5 min) significantly potentiated the hypotensive effect of bradykinin (10 nmol/kg i.v.). This association was significantly attenuated by an antagonist of the B2 receptor. In addition, the hypertensive response to angiotensin I (0.1 nmol/kg i.v.) was significantly reduced by quercetin pretreatment using the same parameters as before. These results suggest an inhibitory effect of quercetin on the angiotensin-converting enzyme activity, similar to that of captopril. Quercetin was equally effective when given orally or intravenously.
authors.affiliation: Departamento de ciencias fisiológicas, Universidade Federal de Santa Catarina, Florianópolis, Brasil.
authors.forename: L P N
authors.initials: LP
authors.lastname: Häckl
authors.forename: G
authors.initials: G
authors.lastname: Cuttle
authors.forename: Sanches S
authors.initials: SS
authors.lastname: Dovichi
authors.forename: M T
authors.initials: MT
authors.lastname: Lima-Landman
authors.forename: M
authors.initials: M
authors.lastname: Nicolau
mesh_terms: D000284:Administration, Oral; D000803:Angiotensin I / Q000494:pharmacology*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D001920:Bradykinin / Q000031:analogs & derivatives* / Q000494:pharmacology*; D065168:Bradykinin Receptor Antagonists; D002216:Captopril / Q000494:pharmacology; D007275:Injections, Intravenous; D008297:Male; D011794:Quercetin / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D065168:Bradykinin Receptor Antagonists; C065679:icatibant; D000803:Angiotensin I; D002216:Captopril; D011794:Quercetin; D001920:Bradykinin