Fig. 1. Morphological evidence of synapse-like structures between hGFAP/EGFP-positive glial cells and neurons. Glial cells in the hippocampal CA1 area of hGFAP/EGFP transgenic mice were immunolabelled by anti-GFP antibodies and visualized by HRP-reaction (A), silver intensified immunogold reaction (B) and post-embedding labelling with immunogold particles (C,D). EGFP-positive profiles in A are visible by dense, black peroxidase reaction product. In B, glial profiles (outlined by arrowheads) are labelled by black silver grains. EGFP-positive presumed GluR cells in A and B are in contact with synaptic nerve terminals. Areas of glial-neuron contact are magnified in the inserts (delineated by dashed rectangles). Scale bar in A, B=0.2 µm and 0.1 µm in inserts. Synapse-like structures in (C,D) display typical synaptic terminals with synaptic vesicles inside the neuronal `partner' and post-synaptic densities (arrowheads) in the labelled EGFP-positive glial profiles. Circles are intended to mark the 12 nm gold particles. There are also mitochondria (mit) and endoplasmic reticulum (black arrow head) in the labelled profiles. Note unspecific gold labelling on mitochondria in (C,D). Scale bars in C,D=0.25 µm.