Regeneration of nerve fibers

Peripheral nerve block is created by injecting ethanol around the selected nerve. The effect of alcohol on nerve tissue has been examined in animal models and in postmortem specimens from patients who received neurolytic blocks (8,9). In general, alcohol causes destruction of nerve fibers, with subsequent Wallerian degeneration. The basal lamina around the Schwann cell usually remains intact. This leaves a tract available for axon regeneration without the formation of a neuroma. If the cell bodies are completely destroyed, regeneration will not occur. Contact of alcohol with unintended nerve roots underlies many of the more serious complications. Involvement of anterior rootlets sufficient to interrupt motor nerve function will result in muscle weakness or paralysis. Interruption of... 

Bijlsma, W.A., Jennekens, F.G.I., Schotman, P. and Gispen, W.H. (1983b) Stimulation by ACTH 4-10 of nerve fiber regeneration following sciatic nerve crush. Muscle Nerve 6 104-112. 

Zapata P, Stensaas LJ, Eyzaguirre C. Recovery of chemosensoiy function of regenerating carotid nerve fibers. In Acker H, Fidone S, Pallot D, Eyzaguirre C, Lubbers DW, Torrance RW, eds. Chemoreception in the Carotid Body. Berlin Springer-Verlag, 1977 44-50. 

Short term L-acetyl carnitine treatment has shown symptomatic benefits in ATN, although it is unclear if this effect is long lasting because of neuronal regeneration or is merely an analgesic effect (Scarpini et al. 1997 Oslo et al. 2006). Longer term studies showed improvements in epidermal nerve fiber density (Hart et al. 2004) as well as the symptoms of neuropathy when patients were treated with L-acetyl carnitine (Hart et al. 2004 Herzmann et al. 2005). A short term randomized, double-blind, placebo-controlled study showed reduction in pain over a 2 week period in HIV patients with TNA (Youle and Oslo 2007). 

This chapter deals with botulinum toxin type A (BOTOX) in the treatment of strabismus, blepharospasm, and related disorders. Botulinum toxin type A (BOTOX) has been used to treat strabismus, blepharospasm, Meige s syndrome, and spasmodic torticollis. By preventing acetylcholine release at me neuromuscular junction, botulinum toxin A usually causes a temporary paralysis of the locally injected muscles. The variability in duration of paralysis may be related to me rate of developing antibodies to me toxin, upregulation of nicotinic cholinergic postsynaptic receptors, and aberrant regeneration of motor nerve fibers at me neuromuscular junction. Complications related to this toxin include double vision (diplopia) and lid droop (ptosis). 

Wendt, J. S., Fagg, G. E., and Cotman, C. W., Regeneration of rat hippocampal fimbria fibers after fimbria transection and peripheral nerve or fetal hippocampal implantation, Exp. Neurol., 79, 452, 1983. 

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