PNS myelin

The specific galactolipids found in PNS myelin are largely the same as CNS myelin, although some glycolipids such as sulphated glucoronyl paragloboside and its derivatives are specific for PNS myelin. The major CNS myelin proteins are also found in PNS myelin, and the main ones that are special to PNS myelin are peripheral myelin protein zero (P0), peripheral myelin protein 22 (PMP22), peripheral nerve P2 protein, and periaxin. P0 is a glycoprotein and a member of the IgCAM superfamily. It...

Developmental function neuronal guidance

The vertebrate brain develops from the embryonic neuroectoderm that lies above the notochord and gives rise to the entire nervous system. The notochord induces neuroectodermal cells to generate neural stem cells and form the neural plate, which in turn forms the neural tube, from which the brain and spinal cord are derived. The neural precursor cells of the neural tube give rise to both neurones and glia in response to multiple inductive signals produced by the notochord, floor plate, roof...

Reactive astrogliosis

All types of brain insults, regardless of aetiology, trigger a complex astroglial response, which is manifested by astrocyte hypertrophy and proliferation. This glial response is defined as reactive astrogliosis (Figure 9.1). Reactive astrogliosis is a defensive brain reaction which is aimed at (a) isolation of the damaged area from the rest of the CNS tissue, (b) reconstruction of the blood-brain barrier, and (c) facilitation of the remodelling of brain circuits in areas surrounding the...

Demyelinating diseases 1071 Multiple sclerosis

Multiple sclerosis (MS) was recognized by the mid 19th century, and already in 1871 Hammond referred to it as a cerebrospinal sclerosis it was Charcot who, in 1877, realized the role of disrupted myelin in the pathogenesis of this disease. MS is an inflammatory demyelinating disease of the CNS, which culminates in progressive neurological deterioration. The aetiology of MS remains elusive, as both genetic predisposition and environmental factors are indicated. The importance of genetic...