Fig. 1.6.14. Dendritic spine (S) in the vicinity of neuronal perikaryon (P), showing three postsynaptic densities (asterisks) which belong to only one large perforated synapse. The spine is surrounded by astrocyte processes (A). Note a neuronal subsurface cistern in the proximity of the spine. Scale = 200 nm. (Mouse, neocortex.) Download the high resolution image.