Ultrastructure of the nerve plexuses of the mammalian intestine: The enteric glial cells

doi:10.1016/0306-4522(81)90135-4

Neuroscience

Volume 6, Issue 3, March 1981, Pages 425-436

https://doi.org/10.1016/0306-4522(81)90135-4 Get rights and content

Abstract

The ultrastructure of the glial cells in the enteric plexuses of the rat, guinea-pig, rabbit, cat and sheep has been investigated by freeze-fracture and by thin-section electron microscopy. In all the ganglia studied, glial cells outnumber neurons. They are readily identified by their shape, position and ultrastructure (particularly the abundant amount of gliofilaments) but could not be subdivided into separate types. They provide a partial sheath to the ganglion neurons (but large areas of neuronal membrane lie directly beneath the basal lamina and collagen fibrils) and have long laminar processes extending between nerve processes. Most nerve processes are in direct membrane-to-membrane contact with each other; the glial cells only separate groups of them and rarely form a sheath around an individual neurite.

The gliofilaments are anchored to conspicuous dense bodies beneath the cell membrane at the surface of ganglia. The possible significance of these systems of gliofilaments (and the high number of intermediate junctions) is discussed in the light of the severe mechanical stresses imposed on the ganglia by the contractile activity of the gut wall.

Numerous specialized contacts, of unknown significance, are found between vesicle-containing nerve varicosities and glial cell bodies or glial processes. In freeze-fracture preparations (cat and guinea-pig), a specific pattern of intramembrane particles allows the cell membrane of the enteric glial cells to be readily identified.

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Ultrastructure of the nerve plexuses of the mammalian intestine: The enteric glial cells

Abstract

Localization of the glial fibrillary acidic protein in astrocytes by immunofluorescence

Brain Res.

The fine structure of ependyma in the brain of the rat

J. Cell Biol.

Junctions between intimately apposed cell membranes in vertebrate brain

J. Cell Biol.

The ultrastructure of Auerbach's plexus in the guinea-pig. II. Non-neuronal elements

J. Neurocytol.

Junctions in the central nervous system of the cat. III. Gap junctions and membrane-associated orthogonal particle complexes (MOPC) in astrocytic membranes

Cell Tissue Res.

Synaptic pattern in the visual cortex of turtle. An electron microscopic study

J. comp. Neurol.

The ultrastructure of the superior cervical sympathetic ganglion of the cat. I. The structure of the ganglion cell processes as studied by serial sections

J. Ultrastruct. Res.

Ultrastructural studies on the synaptology of the inferior mesenteric ganglion of the cat. I. Observations on the cell surface of the postganglionic perikarya

J. Ultrastruct. Res.

Types of nerves in the enteric nervous system

Neuroscience

Fine structure of the myenteric plexus in the guinea-pig ileum

J. Anat.

Innervation of the gastrointestinal tract

Int. Rev. Cytol.

Properties of the enteric nervous system: limitation of access of intravascular macromolecules to the myenteric plexus and muscularis externa

J. comp. Neurol.

The mammalian enteric nervous system: a third autonomic division

An electron-microscopic study of the early outgrowth from chick spinal cord in vitro

Z. Zellforsch. mikrosk. Anat.

Fine structural relationships between neurites and radial glial processes in developing mouse spinal cord

J. Neurocytol.

Penetration of systemically-injected horseradish peroxidase into ganglia and nerves of the autonomic nervous system

J. Neurocytol.

Synaptic profiles in the outgrowth from chicken spinal cord in vitro

Z. Zellforsch. mikrosk. Anat.