Impulses in dorsal spinal nerve rootlets in cats and rabbits arising from dorsal root ganglia isolated from the periphery
✍ Scribed by E. J. Kirk
- Publisher
- John Wiley and Sons
- Year
- 1974
- Tongue
- English
- Weight
- 879 KB
- Volume
- 155
- Category
- Article
- ISSN
- 0021-9967
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
Spontaneous discharges arising within lumbar dorsal root ganglia that had been isolated from the periphery by section of the corresponding spinal nerves were recorded in dorsal spinal nerve rootlets in cats and rabbits. Those dorsal rootlet fibers that were individually isolated had conduction velocities of less than 22 meters/second, i.e., they were Aδ fibers. The chronic preparations had been kept alive for between 1 and 21 days, and spontaneous activity was present in each of them. In acute preparations in which hemorrhage was minimal, spontaneous activity first appeared three to three and one‐half hours after section of the spinal nerve. Spontaneous activity in the dorsal rootlets continued for approximately 25 minutes after physical separation, by dissection, of the active nervous tissue from the remainder of the preparation. The activity was not recorded in either the distal parts of sectioned ventral rootlets or the portion of a sectioned spinal nerve that remained in continuity with its dorsal root ganglion.
It is suggested that the occurrence of these discharges could partly explain the observed differences in the extent and reactivity of cutaneous sensory areas between animals in which dorsal spinal nerve rootlets were sectioned close to the spinal cord and animals in which the corresponding spinal nerves were sectioned distal to their dorsal root ganglia.