Changes in mitochondrial functionality and calcium uptake in hypertensive rats as a function of age.

We studied whether mitochondrial functions and Ca2+ metabolism were altered in Wistar Kyoto normotensive (WKY) and spontaneous hypertensive rats (SHR). Ca2+ uptake was decreased in SHR compared to WKY rats. Accumulation of Ca2+ was more efficient in WKY than in SHR rats. mDeltaPsi was lower in SHR compared to WKY rats. Basal complex IV activity was higher in SHR than WKY rats, whereas basal L-citrulline production, an indicator of nitric oxide synthesis, was decreased in SHR and dependent on Ca2+ concentration (p<0.05). Impact of Ca2+ was counteracted by EGTA. These data show an age-dependent decreased mitochondrial functions in brain mitochondria during hypertension.