Are medium spiny neurons myelinated?

Are medium spiny neurons myelinated?

The axons of one type of medium spiny neuron and the large aspiny neuron were myelinated. The parent axons of the most common type of medium spiny neurons were followed to the globus pallidus and, in some cases, to the internal capsule.

Are medium spiny neurons Glutamatergic?

Striatal medium spiny neurons (MSNs) are contacted by glutamatergic axon terminals originating from cortex, thalamus and other regions. The striatum is also innervated by dopaminergic (DAergic) terminals, some of which release glutamate as a co-transmitter.

What are striatal neurons?

The striatum is the main input nucleus of the basal ganglia and a key neural substrate for procedural learning and memory. The vast majority of striatal neurons are spiny GABAergic projection neurons, which exhibit slow but temporally precise spiking in vivo.

Are MSNs interneurons?

In addition to the GABAergic MSNs, GABAergic interneurons are present within the striatum (see chapter: GABAergic Interneurons of the Striatum).

Is the basal ganglia in the telencephalon?

The basal ganglia comprise a distributed set of brain structures in the telencephalon, diencephalon, and mesencephalon (Figure 4.1 and Table 1). The forebrain structures include the caudate nucleus, the putamen, the nucleus accumbens (or ventral striatum) and the globus pallidus.

Is basal ganglia white or gray matter?

The basal ganglia are a group of grey matter nuclei in the deep aspects of the brain that is interconnected with the cerebral cortex, thalami and brainstem.

What are the phenotypes of medium spiny neurons?

Medium spiny neurons have two primary phenotypes (characteristic types): D1-type MSNs of the direct pathway and D2-type MSNs of the indirect pathway. Most striatal MSNs contain only D1-type or D2-type dopamine receptors, but a subpopulation of MSNs exhibit both phenotypes.

Are medium spiny neurons excitatory or inhibitory?

Since these inputs are glutamatergic they exhibit an excitatory influence on the inhibitory medium spiny neurons. There are also interneurons in the striatum which regulate the excitability of the medium spiny neurons.

Are medium spiny neurons part of the basal ganglia?

Within the basal ganglia, there are several complex circuits of neuronal loops all of which include medium spiny neurons.

What type of neurons are in the striatum?

The striatum is the largest input nucleus of the basal ganglia (BG), a group of interconnected subcortical nuclei [19]. In rodents, most (~95%) neurons within the striatum are γ-aminobutyric acid (GABA)ergic projection neurons called medium spiny neurons (MSNs) (see Glossary ). The remainder are GABAergic and cholinergic interneurons.