Purkinje Cell

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Purkinje cell

[pər′kin·jē ‚sel]
(histology)
Any of the cells of the cerebral cortex with large, flask-shaped bodies forming a single cell layer between the molecular and granular layers.

Purkinje Cell

 

any one of numerous large neurons of the cerebellar cortex whose axons extend beyond the cortex; first described in 1837 by J. E. Purkinje.

Purkinje cells transmit the commands of the cerebellar cortex to its subordinate motor centers, the cerebellar and vestibular nuclei. In mammals and birds, the bodies of Purkinje cells are arranged in the cerebellar cortex in a single layer, called the gangliar, or Purkinje, layer. The Purkinje layer is located between the molecular layer, into which each Purkinje cell extends a dendrite, and the granular layer, through which the axon of a Purkinje cell passes into the white matter of the cerebellum. The flattened dendrite of a Purkinje cell has smooth branches of the first, second, and third orders and short branches (not more than 20 μ long) that are covered with spines. These branches come in contact with the axon endings of the granular cells of the cerebellar cortex; in a cat, for example, there are about 0.2 million synapses per dendrite. The smooth branches of a dendrite and the body of the Purkinje cell come in contact with a convoluted liana-like fiber (one per Purkinje cell) that enters the cerebellum from the inferior olivas and some other nuclei of the medulla oblongata. Both types of synapses are excitatory.

The inhibitory endings of Purkinje cells are formed by intercellular cortical neurons (basket, stellate, and Golgi cells); gamma-aminobutyric acid seems to be the mediator. The same mediator is probably secreted by the axon endings of Purkinje cells onto the neurons of the cerebellar and vestibular nuclei.

The dendrites of Purkinje cells have become progressively more complex and flattened in the course of vertebrate evolution; the total number of Purkinje cells has also increased, totaling 15–20 million in man.

D. A. SAKHAROV

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Se ha descrito que TR[alfa]1 es responsable del desarrollo dendritico de las celulas de Purkinje que depende de la accion de hormona tiroidea.
Greater Dnm1l-stained puncta were found localized with mitochondria, particularly within the ML, with localization to Purkinje dendrites observed by electron microscopy.
lh]) And because we also used the above mentioned optical feature (the distance between the 1st and 4th Purkinje images), we only used one texture feature of [(SD1.
Zinc supplementation does not attenuate alcohol-induced cerebellar Purkinje cell loss during the brain growth spurt period.
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Effects of intracellular calcium ions, verapamil, and lanthanum on active and passive properties of canine cardiac Purkinje fibers.
Ethanol-induced changes in Purkinje cells of rat cerebellum.
Therefore, it can be reasonably postulated that, in mentioned areas such as Prf borderlands, neurons like Purkinje cells can be trapped by different compositions of presynaptic fibers and, consequently, show synaptic heterogeneity even have no difference in postsynaptic receptors (Lambolez et al.
Using the method of differential morphometric analysis (Avrushchenko, 1994) the Purkinje cells of the lateral regions of the cerebellum, neurons of the V stratum of the sensorimotor cortex, pyramidal cells of the CA1 and CA4 sectors of the hippocampus of 10 control and 10 resuscitated animals were studied.
His explanation of the Purkinje effect (the tendency for red stars to grow brighter the longer you look at them) is confusing.
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