Inferior olivary nucleus
The inferior olivary nucleus (ION) is a structure found in the medulla oblongata underneath the superior olivary nucleus. In vertebrates, the ION is known to coordinate signals from the spinal cord to the cerebellum to regulate motor coordination and learning. These connections have been shown to be tightly associated, as degeneration of either the cerebellum or the ION results in degeneration of the other.
| Inferior olivary nucleus | |
|---|---|
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. CFC: Climbing fiber collateral. GC: Granule cell. PF: Parallel fiber. PC: Purkinje cell. GgC: Golgi cell. SC: Stellate cell. BC: Basket cell. | |
Transverse section of medulla oblongata below the middle of the olive. (Inferior olivary nucleus labeled at center right.) | |
| Details | |
| Part of | Olivary body |
| Identifiers | |
| Latin | complexus olivaris inferior, nuclei olivares inferiores |
| MeSH | D000095746 |
| NeuroNames | 748 |
| TA98 | A14.1.04.008 A14.1.04.219 |
| TA2 | 5988, 6021 |
| FMA | 72243 |
| Anatomical terms of neuroanatomy | |
Neurons of the ION are glutamatergic and receive inhibitory input via GABA receptors. There are two distinct GABAα receptor populations that are spatially organized within each neuron present in the ION. The GABAα receptor make-up varies based on where the receptor localizes on the ION neuron. The reason for this spatial distribution is unknown. It has been proposed that the distinct populations of GABAα receptors allows for fine-tuned regulation within the ION.