Table 2.

Ultrastructural 3D measurements of Po synapses in MC-L4/3, S1-L1 or S1-L5a, and comparison with VPM synapses in S1-L4: postsynaptic element

No. of analyzed synapsesSynapses on spines vs dendritic shafts, %PSD shape, %PSD surface area, μm2Synapses per mitochondrionNo. of analyzed spinesSpine head volume, μm3Spines containing spine apparatus, %Spines with a protrusion embedded into the bouton, %Spines with an additional (symmetric) synapse, %
S1 L5a8083 vs 0.17Disc65Range0.01 – 0.251.0566Range0.01 – 0.1927618
Horseshoe16Mean ± SD0.11 ± 0.06Mean ± SD0.06 ± 0.03
Perforated10Median0.1Median0.05
Fragmented9CV0.52CV0.6
S1 L17196 vs 4Disc43Range0.02 – 0.510.968Range0.01 – 0.283133
Horseshoe37Mean ± SD0.16 ± 0.1Mean ± SD0.11 ± 0.06
Perforated17Median0.14Median0.1
Fragmented3CV0.6CV0.58
M1 L3/46994 vs 6Disc41Range0.03 – 0.411.1565Range0.01 – 0.269199
Horseshoe29Mean ± SD0.17 ± 0.08Mean ± SD0.09 ± 0.05
Perforated22Median0.15Median0.09
Fragmented8CV0.5CV0.51
S1 L4 (VPM)12483 vs 0.17Disc49Range0.01 – 0.241.492Range0.004 – 0.18751315
Horseshoe35Mean ± SD0.1 ± 0.05Mean ± SD0.06 ± 0.04
Perforated9Median0.09Median0.06
Fragmented7CV0.5CV0.62