Statistical analysis of CB₁R in the mouse VMH processed by a preembedding immunogold method.

<p>A: 20.5±1.3% of the synaptic terminals/preterminals are CB₁R immunopositive in <i>CB₁R</i>-WT mice. Similar proportion is in Glu-<i>CB₁R</i>-KO (20.8±0.5%, x² = 0.00024, p = 0.9876), lower in GABA-<i>CB₁R</i>-KO (12.4±1.2%, x² = 8.593, p = 0.0034) and virtually disappears in <i>CB₁R</i>-KO mice (3.9±0.6%, x² = 48.61, p<0.0001). A similar area was analyzed for each animal condition (1,467 µm² in <i>CB₁R</i>-WT; 1,562 µm² in Glu-<i>CB₁R</i>-KO; 1,646 µm² in GABA-<i>CB₁R</i>-KO and 1,519 µm² in <i>CB₁R</i>-KO mice). B: CB₁R immunoparticle density after subtraction of background labeling (0.015±0.003 particles/ µm in the VMH of <i>CB₁R</i>-KO) is very close in <i>CB₁R</i>-WT (0.49±0.07), Glu-<i>CB₁R</i>-KO (0.42±0.02, P = 0.7000) and GABA-<i>CB₁R</i>-KO (0.45±0.03, P = 0.7000) mice. C: There is no statistically significant difference between the percentage of CB₁R immunopositive asymmetric synapses in the VMH of <i>CB₁R</i>-WT (27.2±0.7%) and Glu-<i>CB₁R</i>-KO (21.3±2.5%, x² = 0.4189, p = 0.5175) mice. This value practically disappears in <i>CB₁R</i>-KO mice (2.9±2.9%, x² = 15.47, p<0.0001). A similar area was analyzed for each animal condition (1,352 µm² in <i>CB₁R</i>-WT; 1,547 µm² in Glu-<i>CB₁R</i>-KO and 1,274 µm² in <i>CB₁R</i>-KO mice).