Pyramidal cell 627937 216160592 2008-05-31T10:21:19Z Smily 405576 {{Infobox_neuron |neuron_name = Pyramidal cell |image_neuron = GolgiStainedPyramidalCell.jpg |caption_neuron = A human neocortical [[pyramidal neuron]] stained via [[Golgi's method|Golgi technique]]. Notice the apical dendrite extending vertically above the soma and the numerous basal dendrites radiating laterally from the base of the cell body. |location = [[Cerebral cortex|Cortex]] esp. Layers III and V |function = excitatory projection neuron |neurotransmitter = [[Glutamate]] |morphology = Multipolar Pyramidal |afferents = [[Superficial]] cortical layers |efferents = Varies (see text) |GraySubject = 183 |GrayPage = 722 }} A '''pyramidal cell''' (or '''pyramidal neuron''', or '''projection neuron''') is a [[multipolar neuron|multipolar]] [[neuron]] located in the [[hippocampus]] and [[cerebral cortex]]. These cells have a triangularly shaped [[Soma (biology)|soma]], or cell body, a single [[apical dendrite]] extending towards the [[pial]] surface, multiple [[basal dendrite]]s, and a single [[axon]]. Pyramidal neurons compose approximately 80% of the neurons of the cortex, and release [[glutamate]] as their [[neurotransmitter]], making them the major excitatory component of the cortex (see [[synapse]]). The neurons contributing to the [[pyramidal tract]] (alias the [[corticospinal tract]]) are themselves pyramidal neurons, but most pyramidal neurons send axons elsewhere.<ref>[http://williamcalvin.com/LEM/LEMend.htm] (Reference for this sentence only)</ref> In the [[primary motor cortex]], layer V pyramidal cells are extremely large. These cells are called [[Betz cell]]s. Their cell bodies can be as large as 100 micrometers in humans. Typical human pyramidal cell bodies range from 10 to 50 micrometers. Also, any pyramidal cell that faces the opposite direction of a Betz cell (i.e. its longest dendrite faces the opposite direction of all of the other Betz cells) is known as a [[Martinotti cell]]. Pyramidal cells are tall and conical, triangular in tissue sections. Their apex points toward the brain surface and has a thick dendrite with many branches, and small, knobby dendritic spines. The base gives rise to horizontally oriented dendrites, and an axon that passes into the white matter. Pyramidal cells are the output neurons of the cerebrum. They transmit signals to other parts of the CNS. Their axons have collaterals that synapse with other neurons in the cortex or in deeper regions of the brain. ==See also== * [[Cerebral cortex]] * [[Pyramidal tract]] ==References== {{Reflist}} ==External links== * [http://static.howstuffworks.com/gif/brain-neuron-types.gif Diagram] * [http://neuromedia.neurobio.ucla.edu/campbell/nervous/wp_images%5C198_pyramidal_cells.gif Image] * [http://www.trinity.edu/rblyston/MicroA/Lectures/L16pt1-html/sld007.htm Diagram (as part of slideshow)] * {{BrainMaps|pyramidal%20neuron|pyramidal neuron}} {{neuroanatomy-stub}} {{Nervous tissue}} [[Category:CNS neurons]] [[de:Pyramidenzelle]] [[fr:Cellule pyramidale]] [[lt:Piramidinis neuronas]] [[nl:Piramidecellen]] [[ja:錐体細胞 (神経細胞)]] [[sv:Pyramidcell]]