Evaluation the Nutritional Effect of Lavandula angustifolia L. Essential Oil on Normal and High Blood Pressure and Changes of the Aorta in the Rat

Hypertension is a health problem and alternative medicine is offered for its controlling. Nutritional effects of Lavandula angustifolia L. (lavender) oil on high blood pressure (BP), and histological changes of the aorta in rat has been investigated in this study. Therty five male wistar rats were divided into 5 groups; normal, hypertensive and control. Hypertension was induced by daily L-NAME administration in drinking water for 6 weeks and lavender oil (500 mg/kg) or its vehicle was given orally simultaneously. After basal BP measurement, lavender (50 mg/kg, iv) was injected in control groups. Histological evaluation of the thoracic aorta included staining with hematoxylin-eosin and orcein methods. Hypertension induction increased mean arterial BP from 106 to 177 mm Hg and lavender treatment reduced it to 140 mm Hg (P< 0.001). Lavender had no effect on normal rats. Intravenous injection of lavender reduced BP about 75% in normotensive and hypertensive rats (P<0.001). Hypertension induction increased cross-section area, aorta and media thickness, and reduced elastic lamina thickness (P<0.001). Lavender treatment reduced cross-section area of the aorta and media thickness, and increased elastic lamina thickness (P < 0.05). Hypertension and treatment had no effect on advanthia and elastic lamina numbers. Nutritional lavender oil prevented BP increases and pathological changes of the aorta in hypertensive rats. It seems lavender oil is beneficial for prophylaxis of hypertension.