Nerve cell body

Neuroanatomists have taken advantage of the phenomenon of fast retrograde transport to locate remote nerve cell bodies in the CNS of an experimental animal that are connected to an identified axonal fiber tract whose origin is uncertain. The tracer material [purified horseradish peroxidase (HRP) enzyme] is injected in the region of the axon terminals, where it is taken up by endocytosis and then is carried by retrograde axonal transport over a period of several hours to days back to the nerve cell body. The animal is sacrificed, and the enzyme tracer is localized by staining thin sections of the brain for peroxidase activity. 

Hydroxy tryptamine, or serotonin, is a neurotransmitter in the central nervous system (CNS). The nerve-cell bodies of the major serotoninergic neurones are in the midline raphe nuclei of the rostral pons, and ascending fibers innervate the basal ganglia, hypothalamus, thalamus, hippocampus, limbic forebrain, and areas of the cerebral cortex. The serotoninergic system plays an important role in the control of mood and behavior, motor activity, hunger, thermoregulation, sleep, certain hallucinatory states, and some neuro-endocrine mechanisms. 

The gray matter is composed of nerve cell bodies and unmyelinated intemeuron fibers. The location of the gray matter in the spinal cord is opposite to that of the brain. In the brain, the gray matter of the cerebrum and the cerebellum is found externally forming a cortex, or covering, over the internally located white matter. In the spinal cord, the gray matter is found internally and is surrounded by the white matter. 

Ganglion. A general term for a group of nerve cell bodies with a few exceptions these are located outside the CNS. 

Briefly, the flatworm brain is most commonly a ring-like or semicircular structure formed by the connection of two concentrations of nerve axons and nerve cell bodies by a well-developed commissure or commissures. These bilobed accumulations of nerves form the cerebral ganglia that occupy the lateral margins of the brain and comprise a core of nerve axons that are enveloped by a loose gathering of the associated cell bodies at least some flat-worm brains appear to be further surrounded by multilayer sheaths of mesenchyme that represent primitive glia-like cells (Sukhdeo and Sukhdeo, 1994). 

Neuronopathy. Neuronopathy refers to generalized damage to nerve cells, with the primary damage occurring at the nerve cell body. Axonal and dendritic processes die secondarily in response to loss of the cell body. Like other cells in the body, neurons die by one of two processes distinguished by their morphological and molecular features apoptosis and necrosis. (This division is overly simplistic there is much debate... 

In cultured cortical neurons, by confocal microscopy, Lee and colleagues [54] demonstrated a receptor-mediated internalization of fluores-cently labeled D-Ala-deltorphin and a retrograde transport of the peptide within nerve cell bodies that might be involved in mediating some of the longterm transcriptional effects of opioids. 

Ganglion A group of nerve cell bodies located in the peripheral nervous system. 

The SN often associated with the Hu antibody is characterized by primary damage to the nerve cell body. The patient suffers from progressive, painful sensory disturbances evolving subacutely, usually with a Rankin score of 3 within 12 weeks of the onset of symptoms [14]. Presenting symptoms include paresthesia, hypoestesia, and very often proprioceptive loss in the affected areas sensory ataxia is common. The upper limbs are often involved [97], The distribution of the SN is often atypical for peripheral neuropathy. The involvement is usually asymmetrical, especially at the onset of symptoms, and may affect the face or upper limbs only. SN is often the presenting symptom of the PEM/SN syndrome, but signs of CNS involvement usually evolve, and autonomic disturbances are common [36]. 

Grey matter refers to the nerve cell bodies, white matter to the nerve cell fibres. 

Grossman SP, Dacey D, Halaris AE, Collier T, Routtenberg A (1978) Aphagia and adipsia after preferential destruction of nerve cell bodies in hypothalamus. Science 202 537-539. 

Janson AM, Fuxe K, Agnati LF, Kitayama I, Harfstrand A, Andersson K, Goldstein M (1988) Chronic nicotine treatment counteracts the disappearance of tyrosine hydroxylase-immunoreactive nerve cell bodies, dendrites and terminals in the mesostriatal dopamine system of the male rat after partial hemitransection. Brain Res 455 332-345. 

Epelbaum J, Moyse E, Tannenbaum GS, Kordon C, Beaudet A (1989) Combined autoradiographic and immunohistochemical evidence for an association of somatostatin binding sites with growth hormone-releasing factor-containing nerve cell bodies in the rat arcuate nucleus. J Neuroendocrinol 7 109-115. 

Nerve growth factor (NGF) is a polypeptide, a molecule composed of several amino acid units that has a protein-like behavior, but is not as complex as a protein in structure. NGF increases the growth of nerve cells, especially those in the peripheral nervous system, and directs the growth and orientation of nerve cell axons (processes which carry impulses away from the nerve cell body to adjoining dendrites). NGF is one of many growth factors found to be essential in cell division (mitosis), and has been isolated from a variety of cells such as mouse salivary glands and developing nerve tissue. The behavior of NGF resembles that of polypeptide hormones such as insnlin. 

Dendrites—Branched structures of nerve cell bodies which receive impulses from axons and carry them to the nerve cell body. 

Ganglion—Cluster of nerve cell bodies. In vertebrates, found outside of the central nervous system and act as relay stations for impulses. In invertebrates, act as a "central" control. 

The nerve cell body contains a nucleus, a nucleolus, and cytoplasm containing the cell (such as mitochcndria, endoplasmic reticulum, and so on). Unique to the nerve cell body are Nissl bodies, which are rough surfaced vesicles in the endoplasmic reticulum (cytcplaan located near the nucleus), and are involved with protein mthe-sis. Another characteristic stracture of nerve cells are the neurofibrils, which are delicate threadlike structures that help to maintain the shape of the cell, and which transport substances between the cell body and the axcn terminals. The plasma merrrbrane around the cell separates the cytoplasm on the inside of the cell from the extracel-... 

The basic components of the fight-or-flight mechanism are depicted schematically in figure 7-B. As stressful events are perceived at the level of the cortex, lower brain areas become activated. In a sense, the limbic system is put on alert. Should ongoing perception result in a conclusion that there is imminent danger, a burst of excitation emanates from a cluster of nerve cell bodies in the brain stem called the locus coeruleus (LC). The LC has sometimes been called the adrenal gland of the brain. The LC nerve cells, which project to the limbic system, are mediated by the neurotransmitter norepinephrine. 

The tachykinins are a family of small peptides (fewer than 50 residues), each of which has the same amino acid sequence, Phe-X-Gly-Leu-Met-NH2, at the amidated carboxy terminus (Fig. 7.1). Although three primary mammahan tachykinins - substance P, neurokinin A (NkA) and neurokinin B (NkB) - have been recognized, only substance P and NkA have been identified in the lungs and airways. Tachykinins are synthesized in nerve cell bodies, appropriately processed, and then transported by axoplasmic flow to the terminal ramifications of axon dendrites, where they serve their neurotransmitter functions. Both substance P and NkA are derived from transcription and translation of the preprotachykinin I (PPT-I) gene (Nawa et al., 1984 Krause etal., 1987). NkB is derived from a separate gene. 

VIP is synthesized in nerve cell bodies and transported by axoplasmic flow to nerve terminals ganglia containing VIP reactive cell bodies are found in great profusion in the walls of the trachea and major bronchi (Uddman et al., 1978 Dey et al., 1981). Nerves with VIP immunoreactivity have been found in the airways of most mammalian species studied (Springall etal., 1988 Barnes etal., 1991). This immunoreactivity is localized both to nerves and to nglia in the airway wall VIP-containing neurons in the airway predominantly innervate bronchial... 

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