Mechanism of demyelination

  

The Demyelination - Breakdown of the fatty sheaths that surround and electrically insulate nerve fibres. The sheaths provide nutrients to the nerve fibres and are vital to the passage of electrical impulses along them. Demyelination “short-circuits” the functioning of the nerve, which causes loss of sensation, coordination, and power in specific areas of the body. The affected nerves may be within the central nervous system (CNS), compris-ing the brain and the spinal cord, or may be part of the peripheral nervous system, which links the CNS to sense receptors, muscles, glands, and other organs throughout the body.

Patches of demyelination are visible on MRI scans of the brain in people who have multiple sclerosis, a disease with symptoms that include blurred vision, muscle weakness, and loss of coordination. The cause of the demyelination in multiple sclerosis is not known. In many cases of the disease, episodes of demyelination alternate with periods of partial or complete recovery of nerve function.

In the rare disorder encephalomyelitis, there is inflammation of nerve cells in the CNS and sometimes also areas of demyelination along the nerves.