Table 2. Summary of ultrastructural measures in the molecular layer of the cerebellum.
Previously reported measures in the hippocampus CA1 region (Spano et al., 2019) and cerebral cortex (de Vivo et al., 2017) are also shown to facilitate the comparison across regions. All protrusions are defined as spines. In oblique spines the axon-spine interface (ASI) could not be measured because the synapse was oriented obliquely or orthogonally to the cutting plane. Standard deviations for the cortex use a pooled estimate based on two sampled regions. MVB, multivesicular body.
| CA1 (stratum radiatum) | Cortex (M1+S1, layer 2) | Cerebellum | |||||||
|---|---|---|---|---|---|---|---|---|---|
| W | EW | S | W | EW | S | W | EW | S | |
| Total N of dendrites | 37 | 26 | 38 | 54 | 57 | 57 | 29 | 24 | 43 |
| Total N of spines | 2764 | 2139 | 3148 | 2919 | 2616 | 2892 | 1944 | 2050 | 3394 |
|
Total N of spines with synapse (some incomplete/oblique) |
2702 | 2080 | 3037 | 2467 | 2267 | 2415 | 1861 | 1926 | 3066 |
|
Total N spines with synapse with measured ASI |
2552 | 1949 | 2840 | 2180 | 1989 | 2136 | 1766 | 1848 | 3004 |
| ASI (µm2, mean ± std) range (µm2) | 0.128±0.122 0.003–1.033 |
0.130±0.122 0.008–0.764 |
0.120±0.108 0.006–0.672 |
0.299±0.323 0.012–4.019 |
0.290±0.305 0.005–3.543 |
0.248±0.278 0.006–2.038 |
0.187±0.109 0.010–0.702 |
0.158±0.095 0.006–0.569 |
0.174±0.104 0.005–1.113 |
|
Dendrite diameter (µm, mean ± std) |
0.60±0.10 | 0.56±0.06 | 0.57±0.09 | 0.89±0.24 | 0.82±0.20 | 0.86±0.25 | 1.31±0.14 | 1.32±0.16 | 1.38±0.19 |
|
Dendrite length (µm, mean ± std) |
23.3±5.4 | 23.2±6.9 | 21.9±6.8 | 26.8±5.9 | 23.8±7.5 | 23.7±8.0 | 8.19±2.97 | 8.68±3.00 | 8.66±3.92 |
|
Spine density (with/without synapse) by dendrite surface area (#/µm2, mean ± std) |
1.72±0.30 | 2.17±0.33 | 2.00±0.34 | 0.76±0.22 | 0.78±0.23 | 0.84±0.23 | 1.83±0.30 | 2.16±0.44 | 1.97±0.51 |
|
Process density (spines without synapse) by dendrite surface area (#/µm2, mean ± std) |
0.04±0.03 | 0.06±0.06 | 0.07±0.08 | 0.12±0.07 | 0.10±0.06 | 0.15±0.09 | 0.08±0.06 | 0.13±0.07 | 0.19±0.10 |
|
Synapse density (spines with synapse) by dendrite surface area (#/µm2, mean ± std) |
1.69±0.30 | 2.12±0.34 | 1.93±0.32 | 0.64±0.20 | 0.68±0.22 | 0.69±0.19 | 1.76±0.28 | 2.04±0.41 | 1.78±0.46 |
|
Nonperforated synapse density by dendrite surface area (#/µm2, mean ± std) |
1.27±0.26 | 1.72±0.29 | 1.47±0.29 | – | – | – | – | – | – |
|
Perforated synapse density by dendrite surface area (#/µm2, mean ± std) |
0.41±0.13 | 0.36±0.10 | 0.44±0.18 | – | – | – | – | – | – |
|
Synapse density (spines with synapse) by dendrite length (#/µm, mean ± std) |
3.14±0.60 | 3.69±0.50 | 3.41±0.50 | – | – | – | 7.86±1.39 | 9.07±1.73 | 8.29±1.82 |
|
Nonperforated synapse density by dendrite length (#/µm, mean ± std) |
2.38±0.52 | 3.00±0.43 | 2.59±0.35 | – | – | – | – | – | – |
|
Perforated synapse density by dendrite length (#/µm, mean ± std) |
0.77±0.23 | 0.63±0.16 | 0.78±0.31 | – | – | – | – | – | – |
|
Perforated synapses % of synapses per mouse (mean ± std) |
24.5 ± 1.3% | 17.6 ± 1.9% | 23.2 ± 5.3% | – | – | – | – | – | – |
|
Oblique spines % of synapses per mouse (mean ± std) |
4.8 ± 1.7% | 4.7 ± 0.9% | 5.2 ± 2.8% | 8.5 ± 2.2% | 10.8 ± 3.3% | 10.0 ± 1.7% | 7.0 ± 6.0% | 5.6 ± 3.5% | 1.8 ± 2.1% |
| Incomplete synapses (go off the image) % of spines with synapse per mouse (mean ± std) | 1.0 ± 0.9% | 1.7 ± 0.9% | 1.5 ± 1.5% | 2.2 ± 2.2% | 2.8 ± 5.2% | 4.0 ± 4.4% | 0.8 ± 1.5% | 1.2 ± 0.3% | 1.2 ± 0.7% |
|
Spines with spine apparatus % of spines with synapse per mouse (mean ± std) |
8.2 ± 0.7% | 10.1 ± 3.1% | 13.5 ± 3.5% | 30.1 ± 4.0% | 29.2 ± 2.5% | 26.1 ± 4.5% | 2.2 ± 3.6% | 6.4 ± 9.8% | 1.8 ± 3.1% |
|
Spines with endosome/s % of spines with synapse per mouse (mean ± std) |
34.8 ± 9.4% | 42.9 ± 12.4% | 41.3 ± 9.5% | 46.4 ± 11.1% | 67.2 ± 8.0% | 57.5 ± 10.0% | 96.3 ± 7.4% | 98.9 ± 1.5% | 99.8 ± 0.5% |
|
Synapses with coated vesicle % of spines with synapse per mouse (mean ± std) |
2.8 ± 2.2% | 2.9 ± 1.3% | 1.8 ± 1.1% | 2.5 ± 1.8% | 4.3 ± 3.2% | 2.6 ± 1.7% | 1.5 ± 1.9% | 0.2 ± 0.2% | 0.1±0.2% |
|
Synapses with spinula % of spines with synapse per mouse (mean ± std) |
19.4 ± 1.9% | 10.1 ± 3.8% | 14.0 ± 3.2% | 1.7 ± 2.0% | 1.3 ± 1.4% | 1.1 ± 0.5% | 1.6 ± 1.0% | 10.3 ± 13.5% | 22.7 ± 16.6% |
|
Synapses with MVB % of spines with synapse per mouse (mean ± std) |
5.3 ± 2.3% | 2.7 ± 3.2% | 3.4 ± 3.2% | 6.4 ± 3.5% | 6.6 ± 2.9% | 3.3 ± 2.2% | 3.4 ± 4.1% | 5.7 ± 8.0% | 2.8 ± 3.9% |
|
Synapses with presynaptic mitochondrion % of spines with synapse per mouse (mean ± std) |
30.3 ± 2.1% | 30.3 ± 3.7% | 31.6 ± 3.6% | 34.7 ± 4.2% | 35.1 ± 2.1% | 33.7 ± 3.3% | 58.0 ± 1.9% | 61.8 ± 7.5% | 57.3 ± 4.4% |
|
Branched synapses % of spines with synapse per mouse (mean ± std) |
15.0 ± 3.7% | 15.8 ± 4.9% | 13.5 ± 1.6% | 13.9 ± 6.1% | 12.2 ± 3.2% | 13.7 ± 3.1% | 17.8 ± 3.3% | 21.0 ± 7.4% | 14.1 ± 2.4% |