Table 1.
Properties of ]Ca2+] transients, bouton volumes, AZ areas and Cav immunoreactivities in PV+ and mGluR1α+ dendrite-innervating axon terminals
| Dendrite-targeting boutons |
Test | p | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PV+ |
mGluR1α+ |
|||||||||||
| Mean | SD | Median | n | No. of animals | Mean | SD | Median | n | No. of animals | |||
| Peak amplitude of ]Ca2+] transient (300 μm Fluo5F) (G/Gmax) | 0.14 | 0.05 | 0.13 | 26* | 15 | 0.11 | 0.04 | 0.11 | 61* | 23 | MW U test | 0.012 |
| Normalized peak amplitude of ]Ca2+] transient (300 μm Fluo5F)a | 1.20 | 0.41 | 1.12 | 26* | 15 | 1.00 | 0.28 | 0.98 | 61* | 23 | t test | 0.024 |
| Peak amplitude of ]Ca2+] transient (100 μm Fluo5F) (G/Gmax) | 0.21 | 0.10 | 0.22 | 14* | 9 | 0.17 | 0.11 | 0.14 | 21* | 13 | MW U test | 0.100 |
| Normalized peak amplitude of ]Ca2+] transient (100 μm Fluo5F)a | 1.33 | 0.51 | 1.36 | 18* | 12 | 1.04 | 0.25 | 1.03 | 35* | 18 | t test | 0.037 |
| Bouton volume in perfused tissue (μm3) | 0.20 | 0.10 | 0.20 | 67* | 3 | 0.25 | 0.18 | 0.20 | 87* | 3 | MW U test | 0.650 |
| Bouton volume in vitro slices (μm3) | 0.31 | 0.12 | 0.26 | 7 | 5 | 0.20 | 0.12 | 0.18 | 10 | 4 | ||
| Total AZ area in perfused tissue (μm2) | 0.06 | 0.03 | 0.06 | 67* | 3 | 0.09 | 0.05 | 0.08 | 87* | 3 | MW U test | 0.000 |
| AZ area in vitro slices (μm2) | 0.10 | 0.04 | 0.09 | 7 | 5 | 0.09 | 0.03 | 0.09 | 10 | 4 | ||
| Cav2.1 density in AZs (gold/μm2)b | 373 | 47 | 370 | 112 | 5 | 321 | 46 | 325 | 172 | 5 | ||
| Cav2.2 density in AZs (gold/μm2)b | 151 | 30 | 139 | 52 | 4 | 130 | 39 | 130 | 114 | 4 | ||
| Cav2.1 extrasynaptic density (gold/μm2)b | 2.14 | 2.46 | 2.21 | 93 | 5 | 2.88 | 2.64 | 2.23 | 174 | 5 | ||
| Cav2.2 extrasynaptic density (gold/μm2)b | 2.69 | 3.15 | 2.35 | 48 | 4 | 1.02 | 1.26 | 0.75 | 113 | 4 | ||
| Background Cav2.1 density (gold/μm2)b | 2.27 | 1.93 | 2.94 | 132 | 5 | 2.27 | 1.93 | 2.94 | 132 | 5 | ||
| Background Cav2.2 density (gold/μm2)b | 0.66 | 0.33 | 0.62 | 104 | 4 | 0.66 | 0.33 | 0.62 | 104 | 4 | ||
| Cav2.1 NND distance (nm) | 24.7 | 4.0 | 23.3 | 43 | 5 | 24.3 | 4.6 | 23.1 | 72 | 5 | ||
| Cav2.2 NND distance (nm) | 32.1 | 7.2 | 30.3 | 21 | 4 | 32.0 | 8.3 | 28.7 | 40 | 4 | ||
| Docked vesicle density (vesicle/μm2) | 33.1 | 21.1 | 35.5 | 47* | 3 | 21.9 | 17.5 | 22.2 | 49* | 3 | MW U test | 0.010 |
| Membrane proximal vesicle density (vesicle/μm2) | 64.9 | 42.0 | 59.1 | 47* | 3 | 47.3 | 26.6 | 49.9 | 49* | 3 | MW U test | 0.037 |
*Used for the statistical comparisons.
a]Ca2+] transients were normalized to the mean of all measured ]Ca2+] transients of the given cell.
bValues calculated from the medians of 5 (Cav2.1) and 4 (Cav2.2) rats.