Cells and fibers in spinal nerves. III. Is a 1:1 ratio in the dorsal root the rule?

✍ Scribed by J. F. Barnes; H. A. Davenport

• Book ID: 102807169
• Publisher: John Wiley and Sons
• Year: 1937
• Tongue: English
• Weight: 997 KB
• Volume: 66
• Category: Article
• ISSN: 0021-9967
• DOI: 10.1002/cne.900660213

✦ Synopsis

It is commonly believed by many neurohistologists that each cell in the dorsal root ganglia of mammals has a process which divides into a central and a distal branch. This conception of the structure of the dorsal root did not receive confirmation in the data obtained by Davenport and Ranson ('31). I n this study of sacral and coccygeal nerves of rabbit, cat and dog, more cells occurred in the dorsal root ganglia than fibers found in the corresponding dorsal roots. The enumeration of cells and fibers extended to human nerves by Davenport and Bothe ( '34) showed, per 100 cells in the dorsal root ganglion, 78, 102, 85, 95, 97, 89 and 96 fibers in the root in the seven nerves studied. (That all these numbers do not agree to a 1: 1 ratio should be kept in mind.)

I n 1936, Duncan and Keyser reported an agreement between the number of cells and fibers in thoracic dorsal roots of caE. Since this finding differed greatly from the findings of Barnes ( ' 3 5 ) it was mutually agreed to exchange material between the two laboratories and determine the cause of the different results. Barnes had found only thirty-five to fifty-eight fibers (Davenport silver stain) f o r every 100 cells. Duncan and Keyser, using Ranson's pyridine-silver method for fibers, 'Contribution no. 239. Presented in part as a thesis by J. F. Barncs in partial fulfillment of requirements for the degree of Master of Science.