Cochlospermum vitifolium induces vasorelaxant and antihypertensive effects mainly by activation of NO/cGMP signaling pathway.
OBJECTIVE
Cochlospermum vitifolium is a medicinal plant used for the treatment of diabetes, hepatobilary and cardiovascular illnesses. The aim of current study was to determine the in vivo antihypertensive and in vitro functional vasorelaxant mechanism of methanol extract of Cochlospermum vitifolium (MECv) and naringenin (NG).


METHODS
Test material was assayed on rat isolated aorta rings test with- and without-endothelium to determine their vasorelaxant mechanism. Also, the in vivo antihypertensive effect was evaluated on spontaneously hypertensive rat (SHR) model. In addition, presence of NG into the extract was confirmed by reverse phase high performance liquid chromatography (RP-HPLC) analysis.


RESULTS
MECv (120 mg/kg) and NG (50 and 160 mg/kg) showed acute antihypertensive effects on SHR when systolic and diastolic pressure were decreased at 1 h and 24 h after administration, respectively. Vasorelaxant effect of MECv and NG was shifted to the right when endothelium-intact aortic rings were pre-incubated with L-NAME (10 microM) and ODQ (1 microM). Also, NG relaxant curves were displaced to the right in the presence of tetraethylammonium (TEA, 1 mM) and 2-aminopyridine (2-AP, 100 microM) on endothelium-denuded aortic rings.


CONCLUSIONS
Experiments described above showed that MECv play an important role in hypertension regulation through NO synthesis and may be PGI(2) production and potassium channel activation on excessive endothelial dysfunction conditions. Unfortunately, presence of NG into the extract is not significant on bioactivity of the extract; however, this compound could be tested and evaluated as structural scaffold for future drug design for development of antihypertensive agents.
Sánchez-Salgado
Juan Carlos
JC
Facultad de Farmacia, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, Mexico.
Castillo-España
Patricia
P
Ibarra-Barajas
Maximiliano
M
Villalobos-Molina
Rafael
R
Estrada-Soto
Samuel
S
D000818:Animals; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D001013:Aorta, Thoracic / Q000187:drug effects / Q000378:metabolism; D031212:Bixaceae / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D006152:Cyclic GMP / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism; D044950:Flavanones / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D006973:Hypertension / Q000188:drug therapy / Q000503:physiopathology; D008297:Male; D009569:Nitric Oxide / Q000378:metabolism; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D011918:Rats, Inbred SHR; D017208:Rats, Wistar; D015398:Signal Transduction / Q000187:drug effects; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology
D000959:Antihypertensive Agents; D044950:Flavanones; D010936:Plant Extracts; D014665:Vasodilator Agents; D009569:Nitric Oxide; D006152:Cyclic GMP; C005273:naringenin