Background:Aldosterone plays a key role in the development of endothelial dysfunction and hypertension. The regulation of biogenesis and fusion/fission processes of vascular mitochondria has not been examined in aldosterone-induced hypertension. Thereby, we sought to explore in greater depth the role of aldosterone in mitochondrial biogenesis and fusion/fission processes in hypertension and the associated increases in oxidative stress.Methods:Male Wistar rats received aldosterone (1mg/Kg/day) + 1% NaCl as drinking water for 3 weeks.Results:Systolic blood pressure was elevated (p<0.05) in aldosterone-treated rats. eNOS and p-eNOSSer1177protein expression was down regulated (p<0.05) and NADPH oxidase subunit p22phox expression was increased (p<0.05) in aldosterone-treated rats. Expression of mitochondrial biogenesis proteins SIRT1, PGC1α, PPARγ, and TFAM decreased (p<0.05) in aldosterone-treated rats. Protein expression of vascular DRP1, OMA1 and S-OPA1 up regulated (p<0.05) in aldosterone-treated rats. MFN1 and L-OPA1 (p<0.05) decreased in aldosterone-treated animals.Conclusion:The results showed that, in aldosterone-treated rats, hypertension is likely associated with increased oxidative stress in the aorta and with changes in the regulation of two key mitochondrial processes such as biogenesis and fusion/fission processes. The overall mitochondrial alterations observed in the study may play a role in aldosterone-derived vascular oxidative stress and hypertension.