Potentials of the fiber components of the coeliac nerve of the bullfrog

✍ Scribed by Bishop, George H.

• Publisher: Wiley (John Wiley & Sons)
• Year: 1937
• Tongue: English
• Weight: 635 KB
• Volume: 9
• Category: Article
• ISSN: 0095-9898
• DOI: 10.1002/jcp.1030090309

✦ Synopsis

TWO FIQURES

I n the bullfrog, following proper degeneration procedures, Lucas and Miksicek ('36) found fibers arising from cells in the 4th spinal ganglion, and coursing through the coeliac nerve to the viscera, of which no processes central to the ganglion could be observed in either osmic-or pyridine-silver stained sections. No evidence of synapses in the dorsal root ganglion could be obtained. These fibers peripherally are small myelinated and non-myelinated, and comprise the bulk of the 4th eomrnunicating ramus, which in turn forms from one-half to two-thirds of the coeliac trunk. In view of so large a component of small fibers from a dorsal root ganglion to a visceral nerve, apparently lacking in central connections, two questions arise: Whether they in fact have central processes in the dorsal root, unstainable or too small to be visible, and whether they have an afferent or an efferent function.

These and other components of the nerves of this region have been investigated physiologically in an effort to throw light particularly on the first of these questions.

TECHNIC Bullfrogs of about 600 gm. were pithed and the skin removed from the body, the lamina of the spine removed, and the lateral and ventral body wall cut away. I n certain ex- periments the roots were stimulated in situ, in others a