Neuron cells

Toxic effects often disappear after the cessation of the exposure, but they can also be permanent. The tissue s ability to regenerate is one of the most important factors that determines the nature of toxic effects. For example, liver tissue has a remarkable capacity to regenerate, and therefore liver injur> is often reversible. On the other hand, neuronal cells do not regenerate at all, thus neuronal injury is irreversible. It is true that neuronal cells can compensate for possible losses, but only to a minor degree. In particular, chronic effects tend to be irreversible. ... 

The duration of signaling influences how a cell responds to a particular stimulus. For example, brief activation of the MAP kinase cascade in the neuronal cell line, PCI 2, results in proliferation, while sustained... 

Hein L (2006) Adrenoceptors and signal transduction in neurons. Cell Tiss Res 326 541-551... 

Populations of receptors that are excluded from synaptic junctions. These may be distributed over neuronal cell bodies or located around but not directly beneath synapses (perisynaptic). Some receptors have become specialised to setve an extrasynaptic function producing a tonic level of activity in response to ambient levels of neurotransmitter. This tonic current can be used to maintain homeostatic control over neuronal excitation. 

The most widely used DNA vims vectors are derived from adenovirus (Ad) and adeno-associated viius (AAV). Adenoviruses contain a 36-kb double-stranded DNA genome and can infect a broad spectrum of cells, including nondividing cells like hepatocytes and neuronal cells. Ad vectors can be produced at high... 

Neuronal cell deterioration Neuronal cell death... 

Neurodegeneration refers to the processes whereby damaged neuronal cells deteriorate or degenerate and eventually die. 

There are multiple mechanisms known to underlie the neuronal cell damage associated with injury or disease that at least theoretically could be targeted for pharmaceutical intervention. Currently however, there is no clinically available therapeutic agent that can reliably protect the brain from progressive neurodegenerative processes for sustained periods. Due to the extensive amount of preclinical research that has been conducted in recent years, there is a basis for optimism, however, it appears likely that some of these approaches will result in clinically effective therapeutic modalities in the near future. A short overview of some of the investigational approaches to combat neurodegeneration appears below. 

Martin LJ (2001) Neuronal cell death in nervous system development, disease, and injury (Review). Int J Mol Med 7 455—478... 

DAT is predominantly expressed by dopaminergic brain neurons, NET by noradrenergic neurons in the central and peripheral nervous system, and SERT is restricted to the axons of serotonergic neurons, which originate in the raphe nuclei and innervate numerous higher brain regions therefore SERT is widely distributed in the brain. Outside the brain, 5HT transport can be measured on non-neuronal cells (e.g. platelets, lympho-blastoid cells and smooth muscle cells) most of the 5HT appearing in the circulation is taken up by platelets. 

Non-neuronal cells (including astrocytes, mechan-osensory hair cells, macrophages, keratinocytes, endothelial cells of the vascular system, muscle cells, lymphocytes, intestinal epithelial cells and various cell-types of the lungs)... 

Reelin is an extracellular matrix protein, which is secreted by neuronal cells and binds to two lipoprotein receptors (VLDLR and ApoER2) that relay the Reelin signal inside target neurons by docking the tyrosine kinase adapter disabled-1 (Dabl). This allows neurons to complete migration and adopt their ultimate positions in laminar structures in the central nervous system. In... 

Zuber, M.X., Goodman, D.W., Kams, L.R., Fishman, M.C. (1989). The neuronal growth-associated protein GAP-43 induces filopodia in non-neuronal cells. Science 224, 1193-1195. 

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