The consequence of mPTP pore opening is that all small electrolytes equilibrate across the IMM, including cofactors and ions. This will not only lead to the disruption of metabolic gradients between the mitochondria and cytosol, including the release of accumulated calcium, but will also lead to osmotic swelling of mitochondria. The IMM no longer maintains a barrier to protons which leads to dissipation of the proton motive force. The resultant uncoupling of oxidative phosphorylation prevents mitochondria from generating ATP, leading to ATP depletion and increased generation of ROS. Mitochondrial swelling may rupture the OMM by releasing cytochrome c. In turn, cytochrome c initiates cellular apoptosis by activating pro-apoptotic factors. It can therefore be concluded that massive formation of mPTP under pathological conditions causes severe mitochondrial injury and cell death.