Figure 4.
Immunohistochemical characterization of Golgi cell axon terminals. A, Partial colocalization of the glycinergic marker GlyT2 (A1) and the GABAergic marker GAD65 (A2) in the same glomerular structures. Note the characteristic GAD65 presynaptic terminal staining pattern, contrasting with the broader GlyT2-IR. A3, Superposition of A1 and A2, indicating that GlyT2-IR either colocalizes (arrows) or is apposed (asterisks and inset) to GAD65-IR. B, Massive colocalization (arrows) of GAD65-IR (B1) and VIAAT-IR (B2), as seen on superimposed images on B3. C, D, Immunodetection of GlyT2 in lobules X and VI, respectively. Note the comparable staining pattern in the granule cell layer of both lobules. Insets, Higher magnification showing GlyT2-IR profiles likely to be Golgi cell axon terminals (arrows) within a glomerulus. E, F, Glycine and GABA immunodetection in Golgi cell terminal. Both are detected in periglomerular profiles (arrows) of lobules X (E1, E2, E3) and VI (F1, F2, F3). Note that different expression levels are detected within each varicosity. A, B, Single confocal sections; C, D, wide-field CCD camera images; E, F, projection of three confocal sections (0.48 μm between each section). Scale bars: A, B, E, F, 5 μm; C, D, 100 μm; inset in A, 1 μm; insets in C, D, 10 μm.