Neuroglial cells

Ambegaokar SS, Wu L, Alamshahi K, Lau J, Jazayeri L, Chan S, Khanna P, Hsieh E, Timiras PS. (2003) Curcumin inhibits dose-dependently and time-dependently neuroglial cell proliferation and growth. Neuro Endocrinol Lett 24 469 73. 

Using this system, Hamburg (13) could show an acceleration of myelinogenesis by (1,5 to 3 yg/ml) addition. The mechanism whereby influences myelination includes (a) differentiation of the neuroglial cell population responsible for myelin synthesis (38), (b) induction of such differentiated cells to synthesize myelin components, and (c) assembling of the various components to form the complex myelin membrane. Studies are underway to examine the latter possibilities. 

Figure 1.10 Some characteristics of neuroglial cells. A. The neural epithelium derives embry-onally from the ectoderm and differentiates in neuroblasts and neurons and in spongioblasts that will differentiate in astrocytes, oligodendrocytes, and ependymal cells as well as migratory spongioblasts that may give rise to neurons. B. Major functions of neuroglial cells. C. Schematic shape of astrocytes and oligodendrocytes and their respective locations with respect to the neuron. (Courtesy of Dr. S. Oklund.)...

Figure 1.12 Schema of EGF stimulation of astrocyte proliferation and dedifferentiation into neuroblasts. Prolonged exposure to EGF causes astrocytes (taken as representative of neuroglial cells) to proliferate rapidly. It also causes them to lose their neuroglial characteristics, as shown by the decline in the activity of their specific marker enzymes simultaneously, they will also reduce growth rate to control levels. They will eventually acquire precursor cell characteristics to become neuroblasts and neurons. Some of the proliferating astrocytic cells will maintain their characteristics, migrate to their usual location, and fulfill their usual functions.4748 (From Timiras, PS. et al., Mech. Ageing Dev., 126, 3, 2005. With permission.)...

IE intestinal epithelial cells, Mgl microglial cells, DC dendritic cells, CNeur cortical neurons, Ur urine collected, BC B cells, Ngl neuroglial cells, Mel melanoma cells. 

The vitreous humor is a viscoelastic connective tissue composed of small amounts of glycosaminoglycans, including hyaluronic acid, and of such proteins as collagen.The collagen fibrils are anchored directly to the basal lamina, which forms the boimdaries of the lens, the ciliary body epithelium, and the neuroglial cells of the retina. Although the anterior vitreous is cell free, the posterior vitreous contains a few phagocytic cells, called hyalo-cytes, and is sometimes termed the cortical tissue layer. 

Neurons are nerve cells (neurocytes), which, together with neuroglial cells, comprise the nervous tissue making up the nervous system. The neuron is the integral el-... 

Stimulates proliferation of connective tissue cells and neuroglial cells Stimulates proliferation of many cell types Work with PDGF and EGF to stimulate fat cell proliferation Stimulates proliferation of many cell types including fibroblasts, endothelial cells, and myoblasts Stimulates proliferation of T lymphocytes Inhibits cell cycle progression of different cell types Inhibits proliferation of hepatocytes and other cell types Inhibits hepatocyte proliferation... 

Techniques are also available for the separation of various cell types in the central nervous system. Among the most widely used methods to separate neuroglial cells from neurons are the techniques described by Sellinger and Azcurra (1974), but other techniques using acetone-glycerol separation of cells or trypsinization of cell suspensions are also available (see Rose, 1968, for a discussion). Methods for the isolation of myelin, postsynaptic membranes, lysosomes, and the vesicles present within nerve terminals that contain neurotransmitters are also available. Invariably, these preparative methods employ some form of density-gradient centrifugation. 

Fig. 2.6 IsoK is considerably more cytotoxic than HNE. P19 neuroglial cells were treated with various concentration of 15-E2-IsoK or HNE for 24 h and the viability of cells determined by the MTT conversion assay. Percent viability was calculated relative to untreated cells. (Mean + SEMn=8)...

The central nerv ous system of insects consists essentially of a double nerve cord situated ventrally and punctuated by segmental ganglia from which the peripheral ner es arise. The axon of such a nerve measures up to 10 /xm in diameter and is enclosed in a thin non-myelinated lipoprotein sheath. These axons are bundled into nerves which are surrounded by dove-tailed layers of neuroglial cells, and the whole is enclosed by a protein lamella. The polarization of a resting nerve is very similar to that of vertebrate nerve (see Section 7.5.1). On electrical stimulation, successive spikes can be obtained at intervals of a millisecond but the action potentials are propagated only at about 2 m s , i.e. some 50 times slower than in the larger myelinated axons of vertebrates. 

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