Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
, 2 (4 Suppl), 193-202

Synapses in the Central Nervous System

Synapses in the Central Nervous System

S L PALAY. J Biophys Biochem Cytol.


A number of different synapses have been described in the medulla, cerebellar cortex, and cerebral cortex of the rat. All of these possess the same fundamental fine structure as follows: 1. Close apposition of the limiting membranes of presynaptic and postsynaptic cells without any protoplasmic continuity across the synapse. The two apposed membranes are separated by a cleft about 200 A wide, and display localized regions of thickening and increased density. 2. The presynaptic expansion of the axon, the end-foot or bouton terminal, contains a collection of mitochondria and clusters of small vesicles about 200 to 650 A in diameter. Although the significance of these structures in the physiology of the synapse is still unknown, two suggestions are made: that the mitochondria, by means of the relation between their enzymatic activity and ion transport, participate in the electrical phenomena about the synapse; and that the small synaptic vesicles provide the morphological representation of the prejunctional, subcellular units of neurohumoral discharge at the synapse demanded by physiological evidence.

Similar articles

See all similar articles

Cited by 150 PubMed Central articles

See all "Cited by" articles


    1. J Exp Med. 1952 Mar;95(3):285-98 - PubMed
    1. Nature. 1953 Jan 3;171(4340):30-2 - PubMed
    1. Proc Soc Exp Biol Med. 1953 Apr;82(4):675-81 - PubMed
    1. J Histochem Cytochem. 1953 Jul;1(4):188-211 - PubMed
    1. J Histochem Cytochem. 1953 Jul;1(4):212-33 - PubMed