The mitochondrial membrane potential and oxygen consumption in the heart of spontaneously hypertensive rats

We investigated the mitochondrial membrane potential and processes of respiration and oxidative phosphorylation in suspension of cardiac mitochondria from 6 month old spontaneously hypertensive rats (SHR) and Wistar (as a control) male rats. The mitochondrial membrane potential and the speed of oxygen consumption were measured using the method described by M.Brand (1995). Processes of respiration and oxidative phosphorylation in cardiac mitochondria were measured using Oxygraph (Hansatech instruments, Norfolk, England). It has been found that in SHR the mitochondrial membrane potential was lower (-113.76 mV+/-3.65 mV) compared to Wistar rats (DeltaPsim=-152.85 mV+/-13.52 mV, p<0.01). In SHR, the respiration rate in state V2 by Chance and V3 were increased compared to Wistar rats (p<0.001). The respiration control by Chance was depressed by 23.9% in SHR compared to Wistar rats. Our data demonstrate, that SHR have some features of functioning of cardiac mitochondria which distinguish them from the Wistar rats. Our data suggest a functional link between mitochondrial energy supply and arterial hypertension.