Stellate cells

From NeuronBankWiki

Stellate cells are intrinsic neurons named for their star-like shape, which results from dendrites arising in many directions.

Basic information

Stellate neurons are a major source of nitric oxide (NO) in the cerebellar molecular layer.stellate neurons are a critical link between neural activity and blood flow in the activated cerebellum and that NO is the principal effector of their vascular actions.

The three most common stellate cells are the inhibitory interneurons found within the molecular layer of the cerebellum, excitatory spiny stellate interneurons and inhibitory aspiny stellate interneurons.

Anatomy

Spiny stellate cells (spiny dendrites) are excitory, smooth stellate cells are inhibitory.

Act as local interneurones that pass on signals between cells of the same region. Their axons are localised and thus do not project outside cortex.

Dendrites are largely symmetrical with no apical dendrite.

Molecular profile

• Neurotransmitter: spiny neurons such as the stellate cells utilize the neurotransmitter glutamate (glu).

Physiology

Fig. 2: Microcircuitry of the cerebellum. Excitatory synapses are denoted by (+) and inhibitory synapses by (-).
MF: Mossy fiber.
DCN: Deep cerebellar nuclei.
IO: Inferior olive.
CF: Climbing fiber.
GC: Granule cell.
PF: Parallel fiber.
PC: Purkinje cell.
GgC: Golgi cell.
SC: Stellate cell.
BC: Basket cell.

Synaptic Connections

Cerebellar stellate cells synapse onto the dendritic arbors of Purkinje cells.

Cortical spiny stellate cells are found in layer IV. They receive excitatory synaptic fibres from the thalamus and process feed forward excitation to layer IV pyramidal cells. Cortical Spiny Stellate cells have a 'regular' firing pattern. Basket and stellate cells (located in the cerebellar Molecular Layer) contribute inhibitory input to Purkinje cells. Basket cells synapse on the initial segment of the axon. Stellate Cells synapse onto the dendrites.

References

Akgören N, Fabricius M, Lauritzen M (1994) Importance of nitric oxide for local increases of blood flow in rat cerebellar cortex during electrical stimulation.

Barone P, Batardiere A, Knoblauch K, Kennedy H (2000) Laminar distribution of neurons in extrastriate areas projecting to visual areas V1 and V4 correlates with the hierarchical rank and indicates the operation of a distance rule. J Neurosci 20: 3263-81.

Links

[[1]]NIF Stellate cells

[2][pubmed]