Email updates

Keep up to date with the latest news and content from Lipids in Health and Disease and BioMed Central.

Open Access Research

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

Xin-Fang Leong1, Mohd Rais Mustafa2, Srijit Das3 and Kamsiah Jaarin1*

Author Affiliations

1 Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur, Malaysia

2 Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia

3 Department of Anatomy, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur, Malaysia

For all author emails, please log on.

Lipids in Health and Disease 2010, 9:66  doi:10.1186/1476-511X-9-66

Published: 23 June 2010

Abstract

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 < 0.01) in the repeatedly heated oil groups compared to the control and fresh soy oil groups. Consumption of diet containing repeatedly heated oil resulted higher plasma angiotensin-converting enzyme level and lower nitric oxide content and heme oxygenase concentration. Reheated soy oil groups exhibited attenuated relaxation in response to acetylcholine or sodium nitroprusside, and greater contraction to phenylephrine.

Conclusion

As a result of consumption of repeatedly heated soy oil, an elevation in blood pressure was observed which may be due to the quantitative changes in endothelium dependent and independent factors including enzymes directly involved in the regulation of blood pressure.