James C. Jay


Due to improvements in fixation and embedding techniques a restudy of regenerating peripheral nerve was thought advisable in order to better understand and describe the processes which take place.

Femoral nerves of white Wistar rats were used. The lesions were made by either crushing or severing the nerve. After a period of regeneration, varying from 12 hours to six days, the wound was reopened and the injured portion fixed in situ with 1% osmium tetroxide. The tissues were then removed, dehydrated, embedded and sectioned. The sections were stained and studied with a modified RCA EMU2A electron microscope.

Observations revealed that sprouting takes place within at least 12 hours and possibly earlier. Morphologic findings were correlated with those of previous investigators. Particular attention was given to the description of differences in the internal morphology of the reactive Schwann cell and the regenerating axon which had never been described previously. The most striking differences were in 1) the background density of the cytoplasm, 2) size and shape of mitochondria, 3) size of endoplasmic reticulum and 4) size, shape and density of inclusion bodies. Schwann cells were noted to be somewhat phagocytic and frequently were associated with collagen fibers.

It was concluded that 1) in general most features of the regenerating nerve had been described adequately, 2) the regenerating "cone" is not rigid but conforms to the resistances which it meets in its course through the tissues, 3) fibrillar structure is absent in the tip but is found immediately proximal to it, 4) Schwann cells are phagocytic to some degree, 5) Schwann cells may be the origin of collagen within the endoneurium and 6) further study is needed before any definite conclusions can be drawn on the origin and function of the osmiophilic bodies found in the tip and young axon.

LLU Discipline





Graduate Studies

First Advisor

Robert L. Schultz

Second Advisor

Harold Shryock

Third Advisor

Norman M. Case

Fourth Advisor

Walter H. B. Roberts

Fifth Advisor

J. Earl Thomas

Sixth Advisor

Robert W. Woods

Degree Name

Master of Science (MS)

Degree Level


Year Degree Awarded


Date (Title Page)




Library of Congress/MESH Subject Headings

Peripheral Nerves



Page Count

v; 74

Digital Format


Digital Publisher

Loma Linda University Libraries

Usage Rights

This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.


Loma Linda University Electronic Theses and Dissertations

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Loma Linda University. Del E. Webb Memorial Library. University Archives