MS is characterized by demyelination of which tissue in the CNS?

MS is characterized by demyelination of which tissue in the CNS?

• A. Myelin sheath
• B. Grey matter neurons
• C. Blood-brain barrier
• D. Muscle fibers

Answer: (A)

Multiple sclerosis is defined by autoimmune damage to the myelin that wraps CNS axons. The tissue most characteristically demyelinated is the myelin sheath surrounding axons in the central nervous system, which forms the white matter tracts. When this myelin is damaged, nerve impulses conduct more slowly or fail to propagate, producing the diverse neurological symptoms of MS. While grey matter involvement can occur later, the hallmark demyelinated tissue is the myelin sheath around CNS axons. The blood-brain barrier and muscle fibers are not the primary tissues affected by demyelination in MS.

Multiple sclerosis is defined by autoimmune damage to the myelin that wraps CNS axons. The tissue most characteristically demyelinated is the myelin sheath surrounding axons in the central nervous system, which forms the white matter tracts. When this myelin is damaged, nerve impulses conduct more slowly or fail to propagate, producing the diverse neurological symptoms of MS. While grey matter involvement can occur later, the hallmark demyelinated tissue is the myelin sheath around CNS axons. The blood-brain barrier and muscle fibers are not the primary tissues affected by demyelination in MS.