Neuron anatomy

Aston-Jones, G, Shipley, MT, Chouvet, G et al. (1991) Afferent regulation of locus coeruleus neurons anatomy, physiology and pharmacology. Prog. Brain Res. 88 47-73. 

Nematode Neurons Anatomy and Anatomical Methods in Caenorhabditis elegans... 

Moore, RY and Bloom, FE (1978) Central catecholamine neuron systems, anatomy and physiology of the dopamine system. Ann. Rev. Neurosci. 1 129-169. 

The proposal that NO or its reactant products mediate toxicity in the brain remains controversial in part because of the use of non-selective agents such as those listed above that block NO formation in neuronal, glial, and vascular compartments. Nevertheless, a major area of research has been into the potential role of NO in neuronal excitotoxicity. Functional deficits following cerebral ischaemia are consistently reduced by blockers of NOS and in mutant mice deficient in NOS activity, infarct volumes were significantly smaller one to three days after cerebral artery occlusion, and the neurological deficits were less than those in normal mice. Changes in blood flow or vascular anatomy did not account for these differences. By contrast, infarct size in the mutant became larger... 

Moore, R.Y. The anatomy of central serotonergic neuron systems in the rat brain. In Jacobs, B.L., and Gelperin, A., eds. Serotonin Neurotransmission and Behavior. Cambridge, MA MIT Press, 1981. pp. 35-71. 

FIGURE 29-1. Anatomy of the extrapyramidal system. The extrapyramidal motor system controls muscle movement through a system of pathways and nerve tracts that connect the cerebral cortex, basal ganglia, thalamus, cerebellum, reticular formation, and spinal neurons. Patients with Parkinson s disease have a loss of dopamine neurons in the substantia nigra in the brain stem that leads to depletion of dopamine in the corpus striatum. The corpus striatum is made up of the caudate nucleus and the lentiform nuclei that are made up of the putamen and the globus pallidus. 

Moore, R. Y. Bloom, F. E. (1979). Central catecholamine neuron systems anatomy and physiology of the norepinephrine and epinephrine systems. A. Rev. Neurosci. 2, 113-68. 

Wake-sleep-related functional anatomy of mesotelencephalic dopamine neurons... 

Davis, R.E. and Stretton, A.O.W. (1996) The motomervous system of Ascaris electrophysiology and anatomy of the neurons and their control by neuromodulators. Parasitology 113, S99-SI 18. 

FIGURE 26-5 Immunohistochemical localization of type I corticosteroid receptor (mineralocorticoid receptor) in the rat hippocampus. (A) Mineralocorticoid immunoreactivity is concentrated in pyramidal cell fields of the cornu ammonis (CA2). (B) High-power photomicrograph shows that steroid-bound mineralocorticoid receptors are primarily localized to neuronal cell nuclei. (Courtesy of Dr James P. Herman, Department of Anatomy and Neurobiology, University of Kentucky.)... 

Two olfactory systems have evolved in terrestrial vertebrates which differ in both their peripheral anatomy and central projections. The main olfactory system is usually conceived as a general analyzer that detects and differentiates among complex chemosignals of the environment (Firestein 2001). Odors are detected by olfactory sensory neurons located in the main olfactory epithelium (MOE) these neurons project to glomeruli in the main olfactory bulb (MOB). The mitral and tufted neurons abutting these MOB glomeruli then transmit olfactory signals to various... 

Anatomy of the parasympathetic system. The cell bodies of parasympathetic preganglionic neurons are located in the brainstem and the sacral spinal... 

FIGURE 2.2 The anatomy of the neuron. Communication between two neurons occurs at the synapse. The presynaptic neuron produces and releases the neurotransmitter into the synaptic cleft. Four mechanisms (1 ) are important to understand the function of most neurotransmitter systems. The release of neurotransmitter can be modulated via presynaptic receptors (1). The amount of neurotransmitter in the synaptic cleft can be decreased by reuptake into the presynaptic neuron (2) or via enzymatic degradation. Neurotransmitter effects at the target neuron are relayed via fast-acting ion channel—coupled receptors (3) or via slower-acting G protein—coupled receptors (4). Down-stream effects of postsynaptic receptors include the phosphorylation (P) of nuclear proteins. 

The excitatory neurotransmitter glutamate is released upon depolarization by the corticostratial, corticosub-thalamic, subthalamic, and thalamocortical projection neurons. As such, these excitatory neurons are key players in the functional anatomy of the basal ganglia and the CSTC loops. While the activity of these neurons is likely to be important in TS, only limited data are available to evaluate their role in this disease. 

The anatomy of autonomic synapses and junctions determines the localization of transmitter effects around nerve endings. Classic synapses such as the mammalian neuromuscular junction and most neuron-neuron synapses are relatively "tight" in that the nerve terminates in small boutons very close to the tissue innervated, so that the diffusion path from nerve terminal to postsynaptic receptors is very short. The effects are thus relatively rapid and localized. In contrast, junctions between autonomic neuron terminals and effector cells (smooth muscle, cardiac muscle, glands) differ from classic synapses in that transmitter is released from a chain of varicosities in the postganglionic nerve fiber in the region of the smooth muscle cells rather than boutons, and autonomic junctional clefts are wider than somatic synaptic clefts. Effects are thus slower in onset and often involve many effector cells. 

Okay, let s return to the anatomy lesson. At this point, you need only appreciate that your brain is composed of neurons and some supporting cells, called glia. If you were to extract a very small cube of brain tissue see Fig. i—i), you would find it densely packed with cells, blood vessels, and very little else. The neurons are organized into columns of cells and small gatherings, called nuclei or ganglia, which tend to be involved in related functions. For example, some ganglia control movement, some control body temperature, and some control your mood. 

Figure i—i. Top The anatomy of a few brain regions that will be discussed later. Bottom How individual neurons communicate with each other. See text for details. 

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