mPTP - Mitochondrial Permeability Transition Pore
The mPTP pore is formed in the inner mitochondrial membrane under certain pathological conditions as traumatic brain injury and stroke. mPTP is a non-specific pore and allows free passage of <1.5 kDa molecules including proteins.
Today, little is known about the structure. Components of the channel might be TSPO (Translocator protein) and cyclophilin-D.
Regulation and Function:
mPTP is one of the major causes of cell death in a variety of conditions. For example, it is key in neuronal cell death in excitotoxicity, in which overactivation of glutamate receptors causes excessive calcium entry into the cell. MPT also appears to play a key role in damage caused by ischemia, as occurs in a heart attack and stroke.Opening can lead to mitochondrial swelling and cell death through apoptosis or necrosis depending on the particular biological setting. Various factors enhance the likelihood of mPTP opening. In some mitochondria, such as those in the central nervous system, high levels of Ca2+ within mitochondria can cause the MPT pore to open.