Search results
Results From The WOW.Com Content Network
In neuroanatomy, a nucleus (pl.: nuclei) is a cluster of neurons in the central nervous system, [1] located deep within the cerebral hemispheres and brainstem. [2] The neurons in one nucleus usually have roughly similar connections and functions. [3]
Neurons such as Purkinje cells in the cerebellum can have over 1000 dendritic branches, making connections with tens of thousands of other cells; other neurons, such as the magnocellular neurons of the supraoptic nucleus, have only one or two dendrites, each of which receives thousands of synapses.
Nuclei are connected to other nuclei by tracts of white matter. Glia are the supporting cells of the neurons and have many functions not all of which are clearly understood, but include providing support and nutrients to the neurons.
Another area, not on the dorsum of the brainstem, is where the special visceral efferents nuclei reside. These formed from the pharyngeal arches , in the embryo. This area is a bit below the autonomic motor nuclei , and includes the nucleus ambiguus , facial nerve nucleus, as well as the motor part of the trigeminal nerve nucleus.
Supraoptic neurons have typically 1-3 large dendrites, most of which projecting ventrally to form a mat of process at the base of the nucleus, called the ventral glial lamina. The dendrites receive most of the synaptic terminals from afferent neurons that regulate the supraoptic neurons, but neuronal dendrites are often actively involved in ...
In the brainstem, α-MNs and other neurons reside within clusters of cells called nuclei, some of which contain the cell bodies of neurons belonging to the cranial nerves. Not all cranial nerve nuclei contain α-MNs; those that do are motor nuclei, while others are sensory nuclei.
Magnocellular neurosecretory cells in rats (where these neurons have been most extensively studied) in general have a single long varicose axon, which projects to the posterior pituitary. Each axon gives rise to about 10,000 neurosecretory terminals and many axon swellings that store very large numbers of hormone-containing vesicles. [ 3 ]
Such transport of molecules towards and away from the soma maintains critical cell functions. In case of neurons, the soma receives a large number of inhibitory synapses, [6] which can regulate the activity of these cells. It has also been shown that microglial processes constantly monitor neuronal functions through somatic junctions, and exert ...