Basket cells are inhibitory

GABAergic In molecular biology and physiology, something is GABAergic or GABAnergic if it pertains to or affects the neurotransmitter GABA. For example, a synapse is GABAergic if it uses GABA as its neurotransmitter, and a GABAergic neuron produces GABA. A ...

interneuron Interneurons (also called internuncial neurons, relay neurons, association neurons, connector neurons, intermediate neurons or local circuit neurons) are neurons that connect two brain regions, i.e. not direct motor neurons or sensory neurons. ...

s of the

brain A brain is an organ (biology), organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as Visual perception, vision. I ...

, found throughout different regions of the cortex and

cerebellum The cerebellum (Latin for "little brain") is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as or even larger. In humans, the cerebe ...

Anatomy and physiology

Basket cells are multipolar GABAergic interneurons that function to make inhibitory synapses and control the overall potentials of target cells. In general,

dendrites Dendrites (from Greek δένδρον ''déndron'', "tree"), also dendrons, are branched protoplasmic extensions of a nerve cell that propagate the electrochemical stimulation received from other neural cells to the cell body, or soma, of the ...

of basket cells are free branching, contain smooth spines, and extend from 3 to 9 mm. Axons are highly branched, ranging in total from 20 to 50mm in total length. The branched axonal arborizations give rise to the name as they appear as baskets surrounding the soma of the target cell. Basket cells form axo-somatic synapses, meaning their synapses target somas of other cells. By controlling the somas of other neurons, basket cells can directly control the action potential discharge rate of target cells. Basket cells can be found throughout the brain, in among other the cortex, hippocampus, amygdala, basal ganglia, and the cerebellum.

Cortex

In the cortex, basket cells have sparsely branched axons giving off small pericellular, basket-shaped elaborations at several intervals along their length. Basket cells make up 5-10% of total neurons in the cortex. There are three types of basket cells in the cortex, the small, large and nest type: The axon of a small basket cell arborizes in the vicinity of that same cell's dendritic range, this axon is short. In contrast, large basket cells innervate somata in different cortical columns due to a long axon. The nest basket cells are an intermediate form of the small and large cells, their axons are confined mainly to the same cortical layer as their somata. Nest basket cells have "radiating axonal collaterals" between that of large and small basket cells. They are included as basket cells because they are interneurons that perform axo-somatic synapses.

Hippocampus

Hippocampal basket cells target

somata The soma (pl. ''somata'' or ''somas''), perikaryon (pl. ''perikarya''), neurocyton, or cell body is the bulbous, non-process portion of a neuron or other brain cell type, containing the cell nucleus. The word 'soma' comes from the Greek '' σῶμ ...

and proximal

dendrite Dendrites (from Greek δένδρον ''déndron'', "tree"), also dendrons, are branched protoplasmic extensions of a nerve cell that propagate the electrochemical stimulation received from other neural cells to the cell body, or soma, of the ...

s of pyramidal neurons. Similar to their counterparts in the cortex, hippocampal basket cells are also

parvalbumin Parvalbumin (PV) is a calcium-binding protein with low molecular weight (typically 9-11 kDa). In humans, it is encoded by the ''PVALB'' gene. It is not a member of the albumin family; it is named for its size (''parv-'', from Latin ''parvus'' smal ...

-expressing and fast- spiking. In the CA3 region of the hippocampus, basket cells can often form recurrent inhibition loops with pyramidal cells. Projections from a pyramidal cell will innervate the basket cell, which in turn has a projection back onto the original pyramidal cells. Since basket cells are inhibitory, this generates a closed loop that can help dampen excitatory responses.

Cerebellum

In the cerebellum, the multipolar basket cells have branching

s, which are dilated and knotty. Basket cells synapse on the cell bodies of

Purkinje cell Purkinje cells, or Purkinje neurons, are a class of GABAergic inhibitory neurons located in the cerebellum. They are named after their discoverer, Czech anatomist Jan Evangelista Purkyně, who characterized the cells in 1839. Structure T ...

s and make inhibitory synapses with Purkinje cells. Cerebellar basket cell axons fire inhibitory neurotransmitters such as GABA to Purkinje cell axons, and inhibits the Purkinje cell. Purkinje cells send inhibitory messages to the deep cerebellar nuclei and are responsible for the sole output of motor coordination from the cerebellar cortex. With the work of the basket cell, Purkinje cells do not send the inhibitory response for motor coordination and motor movement occurs.

Additional images

Image:Diagram of the Microanatomy of Human Cerebellar Cortex.svg, Microcircuitry of the cerebellum.

Excitatory synapses An excitatory synapse is a synapse in which an action potential in a presynaptic neuron increases the probability of an action potential occurring in a postsynaptic cell. Neurons form networks through which nerve impulses travel, each neuron ofte ...

are denoted by (+) and

inhibitory synapses An inhibitory postsynaptic potential (IPSP) is a kind of synaptic potential that makes a postsynaptic neuron less likely to generate an action potential.Purves et al. Neuroscience. 4th ed. Sunderland (MA): Sinauer Associates, Incorporated; 2008. ...

by (-). Basket cell labeled ''BC''. Image:Cerebellum - biel - high mag.jpg, Cerebellum. Image:BasketCellCerebellum.jpg, Cerebellum Microscopic Photo

External links

Cell Centered Database - Cerebellar basket cell

NIF Search - Basket Cell
via the

Neuroscience Information Framework The Neuroscience Information Framework is a repository of global neuroscience web resources, including experimental, clinical, and translational neuroscience databases, knowledge bases, atlases, and genetic/genomic resources and provides many auth ...

References

{{Cerebellum Neurons Central nervous system neurons