Argan (Argania spinosa) oil lowers blood pressure and improves endothelial dysfunction in spontaneously hypertensive rats.
Traditionally hand-pressed argan oil, obtained from Argania spinosa seeds, is eaten raw in south-west Morocco; its rich composition of tocopherols, MUFA and PUFA make a study of its actions on risk factors for CVD, such as hypertension, interesting. The effects of 7 weeks of treatment with argan oil (10 ml/kg) on the blood pressure and endothelial function of spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto rats were investigated. Systolic blood pressure and heart rate were measured every week by the tail-cuff method and endothelial function was assessed by carbachol (10(-8) to 10(-4) M)-induced relaxations of aortic rings and small mesenteric arteries pre-contracted with phenylephrine. Argan-oil administration reduced the mean blood pressure of SHR after the fifth week of treatment (P<0.05) and increased (P<0.01) the endothelial responses of arteries from SHR. The NO synthase inhibitor, L-N-omega-nitroarginine (3 x 10(-5) M) revealed a greater participation of NO in the relaxant effect after the treatment. When cyclooxygenase (COX) was blocked with indomethacin (10(-5) M), an involvement of COX products in the endothelium-dependent response was characterized. Enzyme immunoassay of thromboxane B2 showed a significant decrease (P<0.05) in the release of thromboxane A2 in both aorta and small mesenteric artery after argan-oil treatment of SHR. Experiments in the presence of the thromboxane A2-prostaglandin H2 receptor antagonist ICI 192,605 (10(-5) M) confirmed this result. Results after incubation with the antioxidants superoxide dismutase and catalase suggested that a decreased oxidative stress might contribute to explain the beneficial effects of argan-oil treatment.
Berrougui
Hicham
H
Departement de Chimie-Biochimie, U.F.R. des Substances Naturelles, Faculte de Medecine et de Pharmacie, Univ Mohamed V Souissi. Rabat, Morocco.
Alvarez de Sotomayor
Maria
M
Pérez-Guerrero
Concepción
C
Ettaib
Abdelkader
A
Hmamouchi
Mohamed
M
Marhuenda
Elisa
E
Herrera
Maria Dolores
MD
D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects / Q000503:physiopathology; D001794:Blood Pressure / Q000187:drug effects* / Q000502:physiology; D002217:Carbachol / Q000494:pharmacology; D002316:Cardiotonic Agents / Q000494:pharmacology; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000503:physiopathology; D005609:Free Radicals / Q000378:metabolism; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D007213:Indomethacin / Q000494:pharmacology; D008297:Male; D017537:Mesenteric Artery, Inferior / Q000187:drug effects / Q000503:physiopathology; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D019335:Nitroarginine / Q000494:pharmacology; D010938:Plant Oils / Q000008:administration & dosage*; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D029632:Sapotaceae / Q000737:chemistry*; D013929:Thromboxane B2 / Q000032:analysis
D002316:Cardiotonic Agents; D016861:Cyclooxygenase Inhibitors; D005609:Free Radicals; D010938:Plant Oils; D019335:Nitroarginine; D009569:Nitric Oxide; D013929:Thromboxane B2; D002217:Carbachol; D019001:Nitric Oxide Synthase; D011451:Prostaglandin-Endoperoxide Synthases; D007213:Indomethacin