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Original Research Article
Evaluation of
Cardiovascular Effects of Edible Fruits of Syzygium
cumini Myrtaceae (L) Skeels in Rats
Edla de A Herculano1,
Cintia DF da Costa1, Amanda KBF Rodrigues1,
João X Araújo-Júnior1,2, Antônio EG Santana2,
Paulo HB França2, Ednaldo de A Gomes1,
Marcos J Salvador3, Flávia de BP Moura4
and Êurica AN Ribeiro1*
1Escola de Enfermagem e
Farmácia, Universidade Federal de Alagoas, 2Instituto
de Química e Biotecnologia, Universidade Federal de
Alagoas, Campus A. C. Simões,Maceió, 3Curso
de Farmácia, BTPB, Departamento de Biologia Vegetal,
Instituto de Biologia, Universidade Estadual de
Campinas, Campinas, 4Instituto de Ciências
Biológicas e da Saúde, Universidade Federal de Alagoas,
Campus A. C. Simões, Maceió, Brasil
*For correspondence:
Email:
euricanogueira@gmail.com;
Tel: +55(82)3214-1789
Received: 16 May 2014
Revised accepted: 18
October 2014
Tropical
Journal of Pharmaceutical Research, November 2014;
13(11): 1 853-1861
http://dx.doi.org/10.4314/tjpr.v13i11.12
Abstract
Purpose: To evaluate the hypotensive,
vasorelaxant and antihypertensive effects elicited by
the hydroalcohol extract from the fruits of Syzygium
cumini (EHSCF) in non-anesthetized rats.
Methods: The rats were anesthetized
and polyethylene catheters were inserted into the lower
abdominal aorta and into the inferior vena cava for
blood pressure measurements and administration of drugs.
After a recovery period of 24 h, EHSCF (0.5; 1; 5; 10;
20 and 30 mg/kg, i.v.) was administered in
non-anesthetized rats. The mean arterial pressure and
the heart rate were recorded. To investigate the effects
of extract, doses EHSCF were administered after
pretreatment with L-NAME, atropine, indomethacin, and
hexamethonium. For measurement of isometric tension, a
concentration-response curve was obtained after
Phenylephrine and KCl (80 mM) pre-contractions. The
bioactive extract was analyzed via mass spectrometry
(MS) fingerprinting using direct electrospray ionization
mass spectrometry (ESI-MS).
Results: EHSCF (0.5; 1; 5; 10; 20
and 30 mg/kg) induced hypotension (-15 ± 1, -14 ± 1, -15
± 1, -13 ± 1, -11 ± 1 and -13 ± 2 %) and bradycardia (-6
± 1, -5 ± 1, -6 ± 1, -14 ± 1, -8 ± 1 and -10 ± 2 %) in
normotensive rats. These responses were attenuated by
pre-treatment with L-NAME, indomethacin, hexamethonium
or atropine. In phenylephrine, pre-contracted mesenteric
rings, EHSCF-induced relaxation (Emax = 54.6
± 4.5 % and pD2 = 2.7 ± 0.1) that were affected by
endothelium removal. EHSCF caused relaxant effect of KCl
(80 mM) pre-contracted rings (Emax = 100 ±
0.2 % and pD2 = 2.2 ± 0.1). This effect was not changed
in denuded rings. A single oral administration of the
extract reduced significant mean arterial pressure in
spontaneously hypertensive rats. ESI-MS/MS analyses of
EHSCF demonstrated that the major constituents of the
analyzed samples coincided with the mass of the malic,
gallic, caffeic and ferulic acids.
Conclusion: The results suggest that
EHSCF induces hypotension probably due to a decrease in
peripheral resistance, mediated by the endothelium.
Bradycardia may be due to indirect cardiac muscarinic
activation. The extract also causes an antihypertensive
effect.
Keywords:
Antihypertensive, Edible fruits, Hypotension, Syzygium
cumini, Vasorelaxation |
