PalkovitsM+2-1971c¶
Notes about [PalkovitsM+2-1971c] 1.
- 1(1,2,3)
M. Palkovits, P. Magyar, and J. Szentágothai. Quantitative histological analysis of the cerebellar cortex in the cat. III. Structural organization of the molecular layer. Brain Research, 34(1):1–18, November 1971. URL: https://linkinghub.elsevier.com/retrieve/pii/0006899371903477, doi:10.1016/0006-8993(71)90347-7, Notes: PalkovitsM+2-1971c.html (this file).
This paper has data about basket and stellate cells and parallel fibers in cat cerebellum.
Data for table Cell counts in different species
The following table has data and references for table Cell counts in different species. Values are the number of cells of the given type in the specified species.
Id |
Cell type |
Species |
Value |
Reference |
|---|---|---|---|---|
pb1 |
basket |
cat |
7.5 x 10^6 |
|
pb2 |
stellate |
cat |
20.9x 10^6 |
The cell counts above are calculated from the data using the Figure is given on page 29 (summary section). Also states that the The granule cell : Purkinje cell ratio was 1700-1800 : 1.
The previous paper in the series [PalkovitsM+2-1971b] states that there are about 1.25 x 10^6 purkinje cells. This paper estimates that the Purkinje cell-basket cell ratio is 1 : 6; the Purkinje cell-stellate cell ratio 1 : 16-17.5. Based on that, there would be about 7.5x10^6 basket cells and 20.9x10^6 stellate cells.
Summary section of paper:
Cell density in the molecular layer of the cat cerebellar cortex calculated for the living state is 43,700/cu.mm. Of these 15% are basket cells, 42.8% stellate cells and 41.2% are glial elements (including endothelial cells, pericytes, etc.). The Purkinje cell-basket cell ratio is 1 : 6; the Purkinje cell-stellate cell ratio 1 : 16-17.5. Of the basket cells 21% are located in the ganglionic layer and 79.9% in the molecular layer. Of the molecular layer basket cells 95% are situated in the deeper half of this stratum. The average length of the basket axons in the transverse plane of the folium is 500-550 um (a distance of 10 Purkinje cells). The average span of their descending side branches in the longitudinal plane of the folium is 300-320 um (a distance of 3-3 Purkinje cell bodies in both directions). Calculations of the average number of Purkinje cell baskets in which the basket axon participates gave unexpectedly low values: 8-9 baskets per axon.
Statistical evaluation of systematic measurements performed on electron micrographs of the molecular layer yielded the following quantitative data for the parallel fibers: the average length of the parallel fibers is 2 mm, their average diameter 0.197 um and in a 1 mm wide longitudinal prism of the molecular layer in the living animal there are 1,374,000 parallel fibers. The average diameter of parallel fibers is slightly greater in the deeper palt of the molecular layer; the difference, although statistically significant, is hardly relevant biologically. The average number of parallel fibers crossing the whole dendritic arborization of a Purkinje cell is roughly 400,000. Calculation based on the average lengths and densities of parallel fiber synaptic thickenings showed that the parallel fiber makes synaptic contact with, on an average, only every fifth (allowing for correction, every 5.5th) Purkinje dendrite arborization which it penetrates during its course. The average parallel fiber would thus contact, in its entire course of 2 mm, 45 Purkinje cells (after correction, 42.5). The number of dendritic spines per Purkinje cells is calculated to be 80,000.