Spinal Cord Histology

General organization

Slide 6 shows a cross section through the spinal cord. Look at the section with the lowest magnification and identify the gray matter (contains large neuronal cell bodies) and the white matter. Also, look at the center and identify the central canal. The following photos show gray and white matter, and the central canal

nerve5.jpg (102183 bytes)

nerve6..jpg (95868 bytes)

Identify: a. Large motor neuron, b. Central canal, c. region of white matter. What types of cells line the central canal?

nerve7.jpg (68983 bytes)


Motor Neurons

The next photographs illustrate motor neuronal cell bodies at higher magnification. Also, there are small capillaries in the field lined by a single endothelial cell (simple squamous epithelium). Compare these fields with an electron micrograph of a neuronal cell body. In this light microscopic view, the dark purple patches in the cytoplasm are called Nissl bodies. The nucleus is clear.

nerve8.jpg (58247 bytes)

nerve9.jpg (57382 bytes)

What is being stained by the Nissl stain?

If you were to look at the EM view of the darkly stained structure in the nucleus (n), what would you expect to see?

Dendrites contain Nissl bodies, but axons do not. Can you find both dendritic and axonal processes in either of these fields? Label them.


Glial Cells

Finally, astrocytes and oligodendroglial cells are evident, especially in the white matter. The following photographs illustrate the two types of glial cells. The astrocytes have the lighter colored, larger oval nuclei. Which cell is responsible for the myelination of fibers in the central nervous system?

nerve10.jpg (23225 bytes)

nerve11.jpg (45883 bytes)


Back to Table of Contents

Last updated: 10/09/04
copyright 1998 Gwen V. Childs, Ph.D.
URL Address: http://microanatomy.net/
Gwen V. Childs, Ph.D., WebMistress
childsgwenv@uams.edu; 501 686-7020