Neurons multipolar

Multipolar neurons have many processes that extend from the cell body (Figure 14.4). However, each neuron has only one axon. Most motor (or efferent) neurons are this type and account for 9% of all neurons. Multipolar neurons have a diversity of shapes. 

Motor neuron Sensory neuron Multipolar interneurons... 

Ganglia Clusters of multipolar neurons surrounded by a capsule of loosely organized connective tissue located outside the central nervous system. [NIH]... 

Figure 1.14 (a) Basic structure of a neurone. A motor neurone is shown, but the basic structure of all the neurones is the same. Dendrites transfer information from other nerves to the neurone, while the axon transfers information from the neurone to other neurones or tissues. The axon is particularly long in motor neurones (Chapter 14). (b) Structures of unipolar, bipolar and multipolar neurones. Unipolar neurones transfer information from tissues or organs to the brain. Multipolar neurones are the most abundant in the nervous system. 

In the scolex ganglion of the tetraphyllid Pelichnobothrium speciosum, where unipolar and multipolar neurones are found, the nerve cell processes have been reported as forming tight junctions which cannot be interpreted as synaptic contacts 260) this anomalous observation clearly requires confirmation. 

The features of a typical multipolar neuron. Illustration by Hans Cassidy. Courtesy of Gale Group. 

The structural classification of a neurons depends upon the number of dendrites extending from the cell body. Multipolar neurons have several dendrites the majority of neurons in the spinal chord and brain are multi-... 

Multipolar neurons have many processes and serve principally as motor neurons. Motor neurons, efferent because they conduct impulses away from the central nervous system (the brain and spinal cord) regulate the function of muscles and glands. Afferent neural pathways that send signals to the (CNS) are generally composed of unipolar neurons. Unipolar neurons also serve as sensory neurons— their filamentous dendritic processes exposed and elaborated into or connected to sensory receptor cells. Intemeurons are neurons that connect neurons along a neural pathway. 

Unipolar, bipolar, and multipolar neurons are best described by... 

The existence of a rest group of neurons that remains unaffected by large lesions of the efferent cerebellar pathways in the kitten has been claimed as evidence in favour of the presence of intrinsic or nucleocortical neurons in the central nuclei (Jansen and Jansen 1955). Many of these neurons were found to be large and to be located in the posterior interposed nucleus. Intrinsic neurons of the cerebellar nuclei have been observed in Golgi preparations of the rat by Chan-Palay (1973a, 1977) as small multipolar neurons in the dentate nucleus. The terminals of these intrinsic, inhibitory neurons on the soma and dendrites of cerebellar nuclear cells were tentatively identified as small... 

I. Some smaller cells in layer Ila lack basal dendrites (Haberly and Price, 1978b) and are reminiscent of dentate granule cells in the hippocampus. Layer III is a thicker but less densely packed cellular layer containing larger pyramidal cells whose dendrites also extend throughout layer I. Layer III also contains large multipolar cells whose dendrites do not enter layer I and other intrinsic neuronal types. Layer III exhibits a superficial... 

Layer III Smooth and neurogliaform, multipolar complex appendage and giant cells The most numerous non-pyramidal cell in layer III are neurons that have relatively few dendritic spines or knobs. These cells are distributed in the middle and deep parts of layer III. The somata and dendrites of this cell type vary considerably. The dendrites emerge from numerous sites on the soma and usually branch once or twice near the soma and then extend radially in all directions with few subsequent bifurcations. The dendritic tree typically respects the boundaries of layer III. The axons of layer III smooth cells are difficult to stain, in contrast to layer I smooth cells, possibly because of myelination. 

Fig. 9.4. Structure of a multipolar cell neuron, which is the one that predominates in nervons system of vertebrates. It varies in shape, especially in the length of the axon and the number of dendrites.

VIP-immunoreactivity is located in bipolar non-pyramidal neurones in stratum radiatum and stratum oriens and multipolar neurones in stratum lacunosum-moleculare of the rat hippocampus (Le-rAnth and Frotscher 1983). Axon terminals of VIP-like immunoreactive non-pyramidal neurones terminate on cell bodies of the pyramidal cells (Le-rAnth et al. 1984). 

Kim Y.-T. and Wu C.-F. 1991. Distinctions in growth cone morphology and motility between monopolar and multipolar neurons in Drosophila CNS culture. /. Neurobiol. 22 263-275. 

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