Experimentally-Induced Metabolic Acidosis Does not Alter Aortic Fatty Streak Formation in High-Cholesterol Fed Rabbits

Document Type: Original Article

Authors

1 Department of Physiology; Isfahan University of Medical Sciences, Isfahan, Iran

2 Water and Electrolytes Research Center, Isfahan University of Medical sciences, Isfahan, Iran

Abstract

Objective(s)
Cardiovascular disease causes a major clinical problem in patients with end stage renal disease. Since metabolic acidosis is very common in patients with end stage renal disease, we aimed to investigate the effect of experimentally-induced metabolic acidosis on serum lipid profile and aortic fatty streak (FS) formation in normal and high-cholesterol fed rabbits.
Materials and Methods
Twenty-four male rabbits were divided into four groups (n=6 each): (1) normal diet (ND): (2) hypercholesterolemic diet (HCD) (1%): (3) ND plus acidemic diet: (4) HCD plus acidemic diet. Metabolic acidosis was induced by adding 0.75% NH4Cl in drinking water. After 4 weeks, blood samples were taken and thoracic aortae were dissected for histological examinations.
Results
Results showed that in the animals who received NH4Cl, metabolic acidosis was successfully induced. Serum total cholesterol and low density lipoprotein (LDL) concentrations in HCD groups were significantly higher than ND groups (P<0.05) and acidosis did not significantly change serum lipid levels neither in ND nor in HCD animals (P>0.05). Histological examination of aortae showed higher mean average grades of pathological evaluation in HCD than ND groups (2.1±0.16 vs. 0±0; P<0.05). Acidosis did not further increase FS formation in HCD groups (P >0.05).
Conclusion
In this model of experimentally-induced metabolic acidosis, acidosis could not increase FS formation in HCD animals and it seems that it does not interfere in progression of atherosclerosis process.

Keywords


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