Subcellular fractionation of hippocampal slices. Hippocampal slices were homogenized (total fraction) and subsequently underwent different centrifugation steps to isolate different subcellular fractions: Micros., light membranes plus microsomes; PSD, postsynaptic density; TSF, Triton-soluble fraction and presynaptic plus extrasynaptic fraction. Blots show two different experiments performed in parallel. Synaptophysin and PSD-95 are used as pre and postsynaptic markers, respectively.