title: Antihypertensive Effect of Syzygium cumini in Spontaneously Hypertensive Rats.
abstract: This study evaluated the in vivo potential antihypertensive effect of hydroalcoholic extract of Syzygium cumini leaves (HESC) in normotensive Wistar rats and in spontaneously hypertensive rats (SHR), as well as its in vitro effect on the vascular reactivity of resistance arteries. The hypotensive effect caused by intravenous infusion of HESC (0.01-4.0 mg/kg) in anesthetized Wistar rats was dose-dependent and was partially inhibited by pretreatment with atropine sulfate. SHR received HESC (0.5 g/kg/day), orally, for 8 weeks and mean arterial pressure, heart rate, and vascular reactivity were evaluated. Daily oral administration of HESC resulted in a time-dependent blood pressure reduction in SHR, with a maximum reduction of 62%. In the endothelium-deprived superior mesenteric arteries rings the treatment with HESC reduced by 40% the maximum effect (E max⁡) of contraction induced by NE. The contractile response to calcium and NE of endothelium-deprived mesenteric rings isolated from untreated SHR was reduced in a concentration-dependent manner by HESC (0.1, 0.25, and 0.5 mg/mL). This study demonstrated that Syzygium cumini reduces the blood pressure and heart rate of SHR and that this antihypertensive effect is probably due to the inhibition of arterial tone and extracellular calcium influx.
authors.affiliation: Laboratory of Pharmacology, Department of Physiological Science, Federal University of Maranhão (UFMA), Avenida dos Portugueses 1966, Bacanga, 65080-805 São Luís, MA, Brazil.
authors.forename: Rachel Melo
authors.initials: RM
authors.lastname: Ribeiro
authors.affiliation: Department of Veterinary Medicine, State University of Maranhão (UEMA), 65055-970 São Luís, MA, Brazil.
authors.forename: Vicente Férrer
authors.initials: VF
authors.lastname: Pinheiro Neto
authors.affiliation: Laboratory of Pharmacology, Department of Physiological Science, Federal University of Maranhão (UFMA), Avenida dos Portugueses 1966, Bacanga, 65080-805 São Luís, MA, Brazil.
authors.forename: Kllysmann Santos
authors.initials: KS
authors.lastname: Ribeiro
authors.affiliation: Laboratory of Pharmacology, Department of Physiological Science, Federal University of Maranhão (UFMA), Avenida dos Portugueses 1966, Bacanga, 65080-805 São Luís, MA, Brazil.
authors.forename: Denilson Amorim
authors.initials: DA
authors.lastname: Vieira
authors.affiliation: Laboratory of Pharmacology, Department of Physiological Science, Federal University of Maranhão (UFMA), Avenida dos Portugueses 1966, Bacanga, 65080-805 São Luís, MA, Brazil.
authors.forename: Iracelle Carvalho
authors.initials: IC
authors.lastname: Abreu
authors.affiliation: Laboratory of Pharmacology, Department of Physiological Science, Federal University of Maranhão (UFMA), Avenida dos Portugueses 1966, Bacanga, 65080-805 São Luís, MA, Brazil.
authors.forename: Selma do Nascimento
authors.initials: Sdo N
authors.lastname: Silva
authors.affiliation: Laboratory of Pharmacology, Department of Physiological Science, Federal University of Maranhão (UFMA), Avenida dos Portugueses 1966, Bacanga, 65080-805 São Luís, MA, Brazil.
authors.forename: Maria do Socorro de Sousa
authors.initials: Mdo S
authors.lastname: Cartágenes
authors.affiliation: Laboratory of Pharmacology, Department of Physiological Science, Federal University of Maranhão (UFMA), Avenida dos Portugueses 1966, Bacanga, 65080-805 São Luís, MA, Brazil.
authors.forename: Sônia Maria de Farias
authors.initials: SM
authors.lastname: Freire
authors.affiliation: Laboratory of Pharmacology, Department of Physiological Science, Federal University of Maranhão (UFMA), Avenida dos Portugueses 1966, Bacanga, 65080-805 São Luís, MA, Brazil.
authors.forename: Antonio Carlos Romão
authors.initials: AC
authors.lastname: Borges
authors.affiliation: Laboratory of Pharmacology, Department of Physiological Science, Federal University of Maranhão (UFMA), Avenida dos Portugueses 1966, Bacanga, 65080-805 São Luís, MA, Brazil.
authors.forename: Marilene Oliveira da Rocha
authors.initials: MO
authors.lastname: Borges