Golgi cells

Overview

(adapted from: http://www.scholarpedia.org/article/Cerebellum#Neuronal_types):

Golgi cells are inhibitory interneurons. There are two sizes of Golgi cells: (I) large ones (somata 9-16 µm in diameter), which are found mainly in the upper part of the granular cell layer, and (2) smaller ones (somata 6-l l µm in diameter), which are found in the lower half of the granular layer. They have extensive radial dendritic trees that extend through all layers of the cortex. They receive input from the parallel fibers in the molecular layer and from climbing and mossy fiber collaterals in the granular layer. Their axons branch repeatedly in the granular layer, where they terminate on granule cell dendrites in the cerebellar glomeruli. There are approximately as many Golgi cells as Purkinje cells.

See Microcircuit of Cerebellar cortex for a diagram of Golgi Cells.

In addition to the connections described above (input from parallel fibers and climbing and mossy fiber collaterals) Golgi cells are also connected to each other via gap junctions [DeZeeuwCI+2-2021] and inhibit each other by synaptic connections [HullC+RegehrWG-2012]. Also, some Golgi cells receive inhibition from deep Cerebellar Nuclei [AnkriL+5-2015].

[LoebnerEE-1989] Fig 2 About the Pseudocerebellum project has arrows for connections between Golgi cells and Basket cells. But according to [DeZeeuwCI+2-2021] connections between Golgi Cells and molecular layer interneuronshave been ruled out. So removing these connections would be an update to the figure to account for more recent data.

Some additional connections needed for [LoebnerEE-1989] Fig 2 are between Golgi cells (both gap junctions and synaptic connections).

Quantity

Cat:

4.2x10^5 [LoebnerEE-1989] Fig 2

The numerical ratio of Golgi cells : Purkinje cells was 1 : 3 [PalkovitsM+2-1971b], p. 30. The total number of Purkinje ceils was 1.2-1.3 million. [PalkovitsM+2-1971a]. These two quantities would mean that the number of Golgi cells would be about 1.25 million / 3, or about 4.17 x 10^5. This is probably the source of data in LoebnerEE-1989 Fig. 2.

Connection to Granule Cells

Divergence

Cat:

5.2x10^3 [LoebnerEE-1989] Fig 2

Convergence

Cat: Unknown. [LoebnerEE-1989] Fig 2.

Gap junctions between Golgi Cells

Described in: [DugueGP-2009+8].

Synaptic inhibition between Golgi Cells

Described in: [HullC+RegehrWG-2012]

Data for table Cells and connections in cat

The following table has data and references for table Cells and connections in cat. Values are either a Cell count, or FO,FI where FO is fan-out (number of target cells each source cell contacts) and FI is fan-in (number of source cells going to each target cell).

Id	Source cell	Cell count or Target cell	Value	Reference
g1	golgi	Cell count	4.2x10^5	[LoebnerEE-1989] 1
g2	golgi	golgi	?, ?	[HullC+RegehrWG-2012] 2
g3	golgi	granule	5.2x10^3, ?	[LoebnerEE-1989] 1

1(1,2)

EE Loebner. Intelligent network management and functional cerebellum synthesis. In Raugh MR, editor, Cerebellar Models of Associative Memory: Three papers from IEEE COMPCON SPRING ‘89, pages 14–19. Research Institute for Advanced Computer Science, NASA Ames Research Center, 1989. PDF: LoebnerEE-1989.pdf, Notes: LoebnerEE-1989.html.

2

Court Hull and Wade G. Regehr. Identification of an Inhibitory Circuit that Regulates Cerebellar Golgi Cell Activity. Neuron, 73(1):149–158, January 2012. URL: https://linkinghub.elsevier.com/retrieve/pii/S0896627311009949, doi:10.1016/j.neuron.2011.10.030, Notes: HullC+RegehrWG-2012.html.