Purification and characterization of rat hippocampal CA3-dendritic spines associated with mossy fiber terminals

Abstract 

We report a revised and improved isolation procedure for CA3-dendritic spines, most of them still in association with mossy fiber terminals resulting in a 7.5-fold enrichment over nuclei and a 29-fold enrichment over myelin. Additionally, red blood cells, medullated fibers, mitochondria and small synaptosomes were significantly depleted. We show by high resolution electron microscopy that this subcellular fraction contains numerous dendritic spines with a rich ultrastructure, e.g. an intact spine apparatus, membranous organelles, free and membrane-bound polyribosomes, endocytic structures and mitochondria. This improved experimental system will allow us to study aspects of post-synaptic functions at the biochemical and molecular level.

Keywords:  Dendritic spine, Mossy fiber, Hippocampus, Nitric oxide synthase, Electron microscopy

Abbreviations:  DS, dendritic spines, EM, electron microscopy, MF, mossy fiber, NOS, nitric oxide synthase, PR, polyribosomes, PSD, post-synaptic densities, SA, spine apparatus, SH, dendritic shaft, TVS, endocytic tubulo-vesicular structures