Anatomy and Embryology

, Volume 171, Issue 2, pp 235–243

Three-dimensional analysis of dendritic spines

II. Spine apparatus and other cytoplasmic components
  • Josef Špaček

DOI: 10.1007/BF00341418

Cite this article as:
Špaček, J. Anat Embryol (1985) 171: 235. doi:10.1007/BF00341418


A total of 342 dendritic spines (193 from the visual and 149 from the cerebellar cortex of the mouse) were analyzed in serial and several hundred of thousands of them in single sections, with respect to the presence and organization of the spine apparatus and other cytoplasmic components. The continuity of the spine apparatus with the smooth endoplasmic reticulum of the dendritic trunk was shown in three-dimensional reconstructions. The dense material of the spine apparatus was divided into “inner dense plate” and “outer dense plate”. The close relationship between the outer dense plate and the postsynaptic density suggests that the spine apparatus functions as a postsynaptic protein synthesizing centre. The material from the outer dense plate could be used for a dynamic extension of the synaptic active zone. An extraspinous spine apparatus of the axon initial segment was partially reconstructed. Polyribosomes were found in all large spines of the visual cortex but were not so frequent in small spines and in Purkinje cell dendritic spines. Microfilamentous network and intermediate filaments occurred in the spines. The smooth endoplasmic reticulum of Purkinje cell dendritic spines was reconstructed. No spine apparatus and dense material were present in these spines.

Key words

Pyramidal cellPurkinje cellDendritic spineSpine apparatusSmooth endoplasmic reticulum

Copyright information

© Springer-Verlag 1985

Authors and Affiliations

  • Josef Špaček
    • 1
  1. 1.Department of PathologyCharles University HospitalHradec KrálovéCzechoslovakia