Topic:Myelin Sheath
The myelin sheath is a protective covering composed of lipid-rich material that surrounds the axons of neurons in horses. It functions to insulate nerve fibers and facilitate the efficient transmission of electrical impulses along the nervous system. The integrity and function of the myelin sheath are essential for maintaining normal neurological function in horses. Research on the myelin sheath in equines explores its development, structure, and its role in various neurological conditions. This page aggregates peer-reviewed research studies and scholarly articles that investigate the composition, formation, and potential disorders associated with the myelin sheath in horses.
Comparative quantitative study of astrocytes and capillary distribution in optic nerve laminar regions. Retinal ganglion cell (RGC) axonal structure and function in the optic nerve head (ONH) is predominantly supported by astrocytes and capillaries. There is good experimental evidence to demonstrate that RGC axons are perturbed in a non-uniform manner following ONH injury and it is likely that the pattern of RGC axonal modification bears some correlation with the quantitative properties of astrocytes and capillaries within laminar compartments. Although there have been some excellent topographic studies concerning glial and microvascular networks in the ONH our knowledge regarding the quantitati...
Determination of functional and morphologic changes in palmar digital nerves after nonfocused extracorporeal shock wave treatment in horses. To determine functional and morphologic changes in palmar digital nerves after nonfocused extracorporeal shock wave (ESW) treatment in horses. Methods: 6 horses. Methods: The medial and lateral palmar digital nerves of the left forelimb were treated with nonfocused ESWs. The medial palmar digital nerve of the right forelimb served as a nontreated control nerve. At 3, 7, and 35 days after treatment, respectively, 2 horses each were anesthetized and nerves were surgically exposed. Sensory nerve conduction velocities (SNCVs) of treated and control nerves were recorded, after which palmar digital ...
Peripheral nerve lesions in a case of equine motor neuron disease. A male 14-year-old Arab horse was pathologically diagnosed as equine motor neuron disease (EMND), which was kept as a breeding horse on a farm in Tokachi district of Hokkaido in Japan. On examination of the peripheral nerves, the most characteristic feature was Wallerian-type degeneration revealed by myelinoclasis associated with myelin ovoids which were sometimes infiltrated by macrophages. The other abnormalities were axonal swellings which were surrounded by thin myelin sheaths. Ultrastructurally, the axonal swelling was due to an accumulation of neurofilaments, and was accompanied by a thi...
Equine laryngeal hemiplegia. Part II. An electron microscopic study of peripheral nerves. The recurrent laryngeal nerves were examined by electron microscopy in five control, four subclinical and four clinical laryngeal hemiplegic horses. In addition, the peroneal nerve was examined in two horses in the latter group. The distally distributed loss of large myelinated fibres in the left recurrent laryngeal nerve seen by light microscopy was confirmed. In addition, active axonal pathology was found to be more evident than indicated by light microscopic investigations. The onion bulb formations observed indicated the repetitive nature of the damaging influence to nerve fibres. Although...
Stringhalt in horses: a distal axonopathy. A detailed investigation of the neuropathology of a horse affected with stringhalt was performed. Qualitative and quantitative light and electron microscopy, and single teased fibre preparations of peripheral nerve demonstrated predominantly axonal degeneration, the stage of which was appropriate for the duration of clinical signs. There was selective involvement of large myelinated nerve fibres. A proximal to distal increase in the severity of pathological changes was present in the peripheral nerves. The long left recurrent laryngeal nerve was the most severely affected, followed in order by...
Central nervous system demyelination in Venezuelan equine encephalomyelitis infection. Arboviruses are important pathogens for both animals and humans. Venezuelan equine encephalomyelitis virus (VEEV) is an arbovirus whose pathogenicity for grey matter structures has been previously studied. To our knowledge, the present study is the first to describe extensive inflammation and demyelination in spinal cord white matter of mice infected with VEEV. To probe a possible immunepathogenesis of white matter alterations in this infection, nude mice and heterozygous controls were similarly infected. Whereas controls still showed inflammatory demyelination, nude mice showed no white matte...
Acid phosphatase activity in mouse brain infected with Venezuelan equine encephalomyelitis virus. The mode of development of Venezuelan equine encephalomyelitis virus and the activity of acid phosphatase in the central nervous system of newborn mice were investigated. Precursor particles appeared to be formed in masses of viroplasm, migrating to the membrane of the Golgi cisterns and vacuoles or to the plasma membrane and being transformed into mature viral particles by budding. Mature viral particles were also found in the lumen of the blood vessels and around the myelin sheath of axons. Increased number of Golgi complexes and depletion of polysomes were the main ultrastructural alteratio...