Association of elevated blood pressure and impaired vasorelaxation in experimental Sprague-Dawley rats fed with heated vegetable oil

BACKGROUND: Poor control of blood pressure leads to hypertension which is a major risk factor for development of cardiovascular disease. The present study aimed to explore possible mechanisms of elevation in blood pressure following consumption of heated vegetable oil. METHODS: Forty-two male Sprague-Dawley rats were equally divided into six groups: Group I (control)--normal rat chow, Group II--fresh soy oil, Group III--soy oil heated once, Group IV--soy oil heated twice, Group V--soy oil heated five times, Group VI--soy oil heated ten times. Blood pressure was measured at the baseline level and at a monthly interval for six months. Plasma nitric oxide, heme oxygenase and angiotensin-converting enzyme levels were measured prior to treatment, at month-three and month-six later. At the end of treatment, the rats were sacrificed and thoracic aortas were taken for measurement of vascular reactivity. RESULTS: Blood pressure increased significantly (p