Abstract
1. The ability of preganglionic axons to re-establish their normal pattern of synaptic connexions with superior cervical ganglion cells has been studied after section of the cervical sympathetic trunk.
2. In vivo stimulation of the last cervical (C8) and the first seven thoracic ventral roots (T1—T7) 3-4 months after section of the trunk produced end-organ responses similar to those observed in normal animals.
3. The pattern of innervation of individual neurones, determined by intracellular recording of synaptic potentials 4-9 months after cutting the sympathetic trunk, was also similar to that observed in normal neurones. Both normal and re-innervated ganglion cells were contacted by pre-ganglionic axons arising from C8 to T7, and each neurone was usually innervated by a contiguous subset of these segments.
4. Re-innervated neurones, as normal cells, were typically dominated by the innervation from a particular spinal cord segment, with the adjacent segments contributing a synaptic influence that decreased as a function of distance from the dominant segment. This was true whether the amplitude of the post-synaptic potential, or the estimated number of contributing axons, was used as the criterion of segmental dominance.
5. Re-innervated neurones, however, showed some abnormalities. The average number of ventral roots contributing innervation to each neurone was reduced from 4·1 to 3·0, and discontinuities in the sequence of innervating segments were more frequent than in normal neurones. Moreover, fewer preganglionic axons contacted each neurone after regeneration.
6. A further difference between normal and re-innervated neurones during the period covered by these experiments was that axons from the more caudal spinal cord segments were less successful in re-establishing contacts with ganglion cells than those from the rostral segments. The more caudal the position of the preganglionic neurones, the more pronounced was this relative deficiency.
7. Although anomalies of ganglion cell innervation were apparent, the basis for the restoration of normal functional effects appears to be the re-establishment of a pattern of innervation of individual neurones similar to that observed in normal ganglia.
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Selected References
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- Bray G. M., Aguayo A. J. Regeneration of peripheral unmyelinated nerves. Fate of the axonal sprouts which develop after injury. J Anat. 1974 Jul;117(Pt 3):517–529. [PMC free article] [PubMed] [Google Scholar]
- DOUGLAS W. W., RITCHIE J. M. The conduction of impulses through the superior cervical and accessory cervical ganglia of the rabbit. J Physiol. 1956 Jul 27;133(1):220–231. doi: 10.1113/jphysiol.1956.sp005580. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Eccles J. C. The action potential of the superior cervical ganglion. J Physiol. 1935 Oct 26;85(2):179–206.2. doi: 10.1113/jphysiol.1935.sp003313. [DOI] [PMC free article] [PubMed] [Google Scholar]
- GUTH L., BERNSTEIN J. J. Selectivity in the re-establishment of synapses in the superior cervical sympathetic ganglion of the cat. Exp Neurol. 1961 Jul;4:59–69. doi: 10.1016/0014-4886(61)90078-4. [DOI] [PubMed] [Google Scholar]
- Landmesser L., Pilar G. Selective reinnervation of two cell populations in the adult pigeon ciliary ganglion. J Physiol. 1970 Nov;211(1):203–216. doi: 10.1113/jphysiol.1970.sp009275. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Langley J. N. Note on Regeneration of Prae-Ganglionic Fibres of the Sympathetic. J Physiol. 1895 Jul 18;18(3):280–284. doi: 10.1113/jphysiol.1895.sp000566. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Langley J. N. On axon-reflexes in the pre-ganglionic fibres of the sympathetic system. J Physiol. 1900 Aug 29;25(5):364–398. doi: 10.1113/jphysiol.1900.sp000803. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Langley J. N. On the Regeneration of Pre-Ganglionic and of Post-Ganglionic Visceral Nerve Fibres. J Physiol. 1897 Nov 20;22(3):215–230. doi: 10.1113/jphysiol.1897.sp000688. [DOI] [PMC free article] [PubMed] [Google Scholar]
- MURRAY J. G., THOMPSON J. W. The occurrence and function of collateral sprouting in the sympathetic nervous system of the cat. J Physiol. 1957 Jan 23;135(1):133–162. doi: 10.1113/jphysiol.1957.sp005700. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Njå A., Purves D. Specific innervation of guinea-pig superior cervical ganglion cells by preganglionic fibres arising from different levels of the spinal cord. J Physiol. 1977 Jan;264(2):565–583. doi: 10.1113/jphysiol.1977.sp011683. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Passatore M., Pettorossi V. E. Efferent fibers in the cervical sympathetic nerve influenced by light. Exp Neurol. 1976 Jul;52(1):66–82. doi: 10.1016/0014-4886(76)90201-6. [DOI] [PubMed] [Google Scholar]
- Purves D. Competitive and non-competitive re-innervation of mammalian sympathetic neurones by native and foreign fibres. J Physiol. 1976 Oct;261(2):453–475. doi: 10.1113/jphysiol.1976.sp011568. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Purves D. Functional and structural changes in mammalian sympathetic neurones following interruption of their axons. J Physiol. 1975 Nov;252(2):429–463. doi: 10.1113/jphysiol.1975.sp011151. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Raisman G., Field P. M., Ostberg A. J., Iversen L. L., Zigmond R. E. A quantitative ultrastructural and biochemical analysis of the process of reinnervation of the superior cervical ganglion in the adult rat. Brain Res. 1974 May 10;71(1):1–16. doi: 10.1016/0006-8993(74)90187-5. [DOI] [PubMed] [Google Scholar]