Strokes, head injury and neuronal cell death. An overview.
What we are interested in here is why events such as head injuries and strokes are such a nightmare to treat.
Lets give an example a face. John, 34 years old from Chicago take a diving leap whilst playing goal, cracks his head and severs a major cerebral artery. Uh oh! We have blood haemorrhaging and clearly not being directed where it should be going, a lack of oxygen essentially causes death of neurons and consequently brain damage… right? Sadly for John that isn’t the end of it. The neurons will also release high concentrations a molecule responsible for triggering electrical impulses in the brain (Glutamate). The result is a spreading wave of excitaion in the brain, releasing other mediators that further induce excitation and eventually more cell death due to over excitation (excitotoxicty). There are so many things going on here, calcium increase causes enzymes that digests proteins, mitochondria stop producing power for the cell. It’s a mess.
Restore the blood supply and everything returns to normal? Nope, further damage is inflicted to a wider area of the brain as free radicals such as superoxides cause trouble shooting around in new found freedom.
Picture: Brain Nerve Cells, Light micrograph.
