Figure 6.

Electron microscopy analysis of P2Y₁ receptor on synaptic terminals forming varicosities. In A, labelled varicosities are apposed to neuronal elements of cerebellar cortical layers, mostly dendrites in granule cell layer. In a few cases, the immunoreactivity is so strong to cover the vesicles of the terminal. In B, the features of the varicosities are unchanged also in Purkinje cell layer. In C, the absence of synaptic junctions is clearly visible (see arrow). In D, the granule cell shows specific labelling in the cytoplasm (n = nucleus of granule cell). In E, a few granule cells (GC) are labeled, being on the contrary apposed to immunolabeled terminals. In F, also Purkinje neurons are immunolabeled, especially proximal dendrites (D). Scale bar in A-C = 1 μm; in D = 1,2 μm; in E and F = 0,8 μm.