Monday, September 10, 2012

The Death of a Neuron

          Within the two modules read, we were informed of the living neuron. The active neurons who receive information and transmit information to other cells and which every normal being possesses. There are specialized types of neurons and their structures, shapes, and sizes vary depending on their function. Neurons are composed of important parts, which allow for fast and accurate transfers of messages.

     The proceeding video briefly explains the important parts in a neuron
and it's basic functions.

 
The image of Neuron Architecture
 
                 A topic not covered in these specific modules and which I found very interesting and wanted to research further, was not only the living aspect of a neuron, but also it's death. Neurons are the longest living cells in the body, but many of them die during differentiation and migration. Some diseases of the brain are the result of the unnatural deaths of neurons.
           For example:
 - In Parkinson’s disease, neurons that produce the neurotransmitter dopamine die off in the basal ganglia, an area of the brain that controls body movements. The brain can no longer control the body and people shake and jerk in spasms.

- In Huntington’s disease, a genetic mutation causes over-production of a neurotransmitter called glutamate, which kills neurons in the basal ganglia. As a result, people twist and writhe uncontrollably.

- In Alzheimer’s disease, unusual proteins build up in and around neurons in the neocortex and hippocampus, parts of the brain that control memory. When these neurons die, people lose their capacity to remember and their ability to do everyday tasks. Physical damage to the brain and other parts of the central nervous system can also kill or disable neurons.

- Severe brain injury or stroke can kill neurons outright or slowly starve them of the oxygen and nutrients they need to survive.

- Spinal cord injury can disrupt communication between the brain and muscles when neurons lose their connection to axons located below the site of injury. These neurons may still live, but they lose their ability to communicate.
The image of a diseased neuron
One method of cell death results from the release of excess glutamate.

The image of a dying neuron
Macrophages (green) eat dying neurons in order to clear debris.
 

3 comments:

  1. This is a very interesting topic. Neuronal death is regionally variable with heavy losses of neurons (up to 80%) found in hippocampus and other limbic regions of cortex. I liked that you mentioned the different diseases that can affect our brain and how the death of the neurons occur. Good job!

    ReplyDelete
  2. Neuronal Death is an interesting topic, and the way you defined its different disease was fascinating. The one that caught my attention was the Parkinson’s disease in which the neurotransmitters dopamine die off and in which the area of the brain that controls the movement dies as well. Know I can see how the body can’t control and that is why people shake and have those spasms.

    ReplyDelete
  3. Well done, it is much more appealing to read about neuronal death the way you described it separately by each disease. It really helps in learning about what affect the disease has on human beings as well. For example in the Huntington's disease, we see that because of the genetic mutation, the neurons in the basal ganglia (which is associated with voluntary motor control) are exterminated and as a result "people twist and writhe uncontrollably."

    ReplyDelete