Objectives: This study was designed to determine the morphometric and histological changes of the wall of the thoracic aorta in high salt-fed adult Wistar rats and the possible ameliorative effects of aqueous extract of garlic (Allium sativum).Methods: Twenty-five healthy female Wistar rats weighing 130-180 g were randomly assigned into five groups of five rats each (Groups A, B, C, D and E). Rats in Group A were fed with standard laboratory pellets, while Groups B, C, D and E were fed on the high-salt diet for five weeks. Thereafter, daily administration of 50 mg/kg, 100 mg/kg and 150 mg/kg of the garlic extract were giving orally to Groups C, D and E, respectively for 3 weeks while rats in Groups A and B were administered distilled water. The thoracic part of descending aorta at the level of (T6-T7) was excised for histological studies. Paraffin sections were stained with haematoxylin and eosin, Masson's trichrome and Verhoeff-Van Gieson stains. One-way ANOVA was used to analyze data, followed by Student-Newman-Keuls (SNK) test for multiple comparisons.Results: High salt diet causes significant histomorphological changes on aorta of rats as evidenced by increase in tunica intima, media and adventitia of the aortic wall and decrease in luminal diameter; these findings were reversed by aqueous garlic extract administration. Conclusion:High salt diet increased the thickness of aortic wall and decreased luminal diameter which were significantly reversed by oral administration of garlic extract.

Objectives: The aim of this study was to evaluate the beneficial effect of aqueous extract of garlic (Allium sativum) on the morphology of myocardium of left ventricle in high salt-fed diet Wistar rats.Methods: Twenty-five female Wistar rats weighing 130-180 g were divided into five groups (n=5, each). Group A were fed with standard laboratory pellets, while Groups B, C, D and E were fed a high-salt diet for five weeks. Following this, daily administration of aqueous garlic extract was done orally to Groups C, D and E, respectively for 3 weeks. The left ventricle of the heart was excised, processed in paraffin wax and stained with haematoxylin and eosin, Masson's trichrome and Verhoeff-Van Gieson stains. One-way ANOVA was used to analyze data, followed by Student-Newman-Keuls (SNK) test for multiple comparisons. Results:We found that the relative change in heart weight in the high salt-fed group was lower, though not statistically significant (p=0.175) than the control group. There was significant increase (p<0.05) in plasma levels of sodium and potassium in Group B when compared with control, but this was dose-dependently reversed by aqueous garlic extract in Groups D and E. Histological and histochemical results revealed morphological alterations in the left ventricle of Group B which were also reversed in Groups D and E. Conclusion:The results of this study indicate that high salt diet-induced histochemical and histomorphological changes in the left ventricle of Wistar rats were significantly reversed by oral administration of garlic extract.