CNS activation following peripheral sympathectomy

Many studies have demonstrated that ablation of the sympathetic nervous system (SNS) alters subsequent immune responses. Researchers have presumed that the altered immune responses are predominantly the result of the peripheral phenomenon of denervation. We, however, hypothesized that chemical sympathectomy will signal and activate the central nervous

system (CNS).

Dual-antigen labeling demonstrates that

corticotrophin releasing factor (CRF)-containing neurons in the PVN are

activated by chemical sympathectomy; however, neurons containing

neurotransmitters which may modulate CRF neurons, such as vasopressin,

tyrosine hydroxylase, and adrenocorticotropin, do not coexpress Fos. Our

findings suggest an involvement of the CNS in sympathectomy-induced

alterations of immunity.

Brain, Behavior, and Immunity

Volume 12, Issue 3, September 1998, Pages 230-241

Cervical sympathectomy affects the lower extremities, providing further evidence that the effects of this procedure is not local or limited

Bilateral cervical sympathectomy reduced mechanical allodynia and cold allodynia in the rat

model of neuropathic pain suggesting that neuropathic pain, although the lesions are localized in low extremities, may be correlated with functional disturbance of sympathetic nerve fibers of supraspinal or brain level and help explain the mechanism of neuropathic pain.

Korean J Anesthesiol. 1999 Feb;36(2):327-334. Korean.

Effect of cervical sympathectomy and circulatory hypoxia on time course of prostaglandin concentration in brain tissues

http://www.springerlink.c...ontent/j705306763158841/

Some workers suggest a possible "transmembrane" role of PG in the nervous system.

If the increase in the PG level during ischemia is regarded as a protective reaction, it must be admitted that no increase took place 1 day after CSE (cervical sympathectomy) and it was considerably weakened 7-40 days after CSE.

The effect of cerebral ischemia was virtually indistinguishable from the action of CSE itself.

It can be tentatively suggested that PGF plays the main role in the regulation of tone of the vascular wall and in the regulation of metabolism under conditions of ischemia when the sympathetic regulation is disturbed.

Correlation between Changes in Regional Cerebral Blood Flow and Pain Relief in Complex Regional Pain Syndrome

Objective: Analyzing changes in regional cerebral blood flow (rCBF) with SPECT in complex regional pain syndrome type 1 (CRPS 1), formerly known as reflex sympathetic dystrophy, is an optimal method for evaluating effective pain relief. We attempted to investigate the correlation of changes in rCBF with pain relief during treatments of sympathetic blockade and multimodal epidural pain control.

Case Report: We describe a patient with severe CRPS 1 in whom conventional treatment failed to relieve the pain.

Combined repeated lumbar sympathetic blocks and long-term epidural morphine, bupivacaine, and ketamine administration provided satisfactory pain relief and functional activity recovery. Six normal control subjects having one Tc-99m HMPAO scan each and the patient with CRPS having 3 Tc-99m HMPAO scans (once before treatment and twice at 4 months and 6 months after treatment, respectively). The patient with CRPS showed lower rCBF than normal

controls in the left thalamus and higher rCBF than normal controls in the right parietal lobe and left frontal lobe.

After subsequent treatment, the subtraction images showed increased rCBF in the left thalamus and decreased rCBF in the right parietal and left frontal lobes.

Conclusions: Tc-99m HMPAO SPECT showed a relationship of rCBF in the thalamus, parietal lobe, and frontal lobe with pain relief. rCBF alterations may provide an indicator for the quality of pain management for neuropathic pains.

Subtraction analysis between pre- and posttreatment, by using statistical parametric mapping (version 2), can be used as an objective indicator for the effectiveness of therapy.

postsympathectomy neuralgia is frequent

Surgical sympathectomy has a long heritage for the treatment of peripheral vascular disease and various chronic pain problems.

Despite concerns expressed as long ago as 1942 about the efficacy of surgical sympathectomy for the management of non-cancer pain, the procedure was enthusiastically pursued for the management of reflex sympathetic dystrophy or complex regional pain syndrome (CRPS), migraine, dysmenorrhea, epilepsy, chronic pancreatitis, postherpetic neuralgia of the trigeminal nerve, postdiscectomy syndrome, and phantom limb pain. However, systematic reviews have found no tangible evidence supportive of sympathectomy for the management of neuropathic pain. Furthermore, postsympathectomy neuralgia is a common complaint with a reported incidence between 15% to 50%.

As surgery is often mentioned as a cause of CRPS, it is somewhat illogical to consider surgery as an effective treatment. Nonetheless, surgical sympathectomy has a long anecdotal history in the treatment of RSD, and more recently endoscopic and radiofrequency sympathectomy has been tried.

Bonica's Management of Pain,

Lippincott Williams & Wilkins, 2009 - 2064 pages

interrupting sympathetic tone to the human brain - ETS

Sweating after sympathetic surgery is a reflex cycle between the sympathetic system and the anterior portion of the hypothalamus according to our investigations. Reflex sweating will not happen if hand sweating can be stopped without interrupting sympathetic tone to the human brain.
http://www.hyperhidrosis.com/symposium.htm

Sympathectomy Causes Aggravated Lesions and Dedifferentiation

http://content.karger.com/ProdukteDB/produkte.asp?Doi=93010

Degeneration patterns of postganglionic fibers following sympathectomy

Seven weeks after surgery, fragments of folded basement lamella and Remak bundles with condensed cytoplasm and numerous flat processes are persisting signs of the degeneration.

In addition to the differences in time course between the proximal and the distal site of observation, it was also noted that both the axonal degeneration and the reactions of the Schwann cells are more pronounced in the rcg than in the muscle nerve. For example there was abundant mitotic activity in the central endoneural and Schwann cells whereas we could not detect such activity in the periphery.

It is concluded that the time course of degeneration and the intensity of the degenerative and reactive processes is, to a considerable extent, determined by the distance between the site of nerve section and the site from which the specimen is taken. Many of the conflicting data in the literature can be explained by this finding.

http://www.ncbi.nlm.nih.gov/pubmed/4051190

Sympathectomy induces adrenergic excitability of cutaneous C-fiber nociceptors

http://www.ncbi.nlm.nih.gov/pubmed/8822575

J Neurophysiol. 1996 Jan;75(1):514-7.

pH changes in synovial fluid following perivascular sympathectomy

Proc Inst Med Chic. 1947 Nov 15;16(17):465.

http://www.ncbi.nlm.nih.gov/pubmed/18896440

Sympathectomy induces mast cell hyperplasia

Long-term superior cervical sympathectomy induces mastcell hyperplasia and increases histamine and serotonincontent in the rat dura mater.

Neuroscience. 2000;96(1):205-13.

Mast cell hyperplasia is found in different pathologies such as chronic inflammatory

processes, fibrotic disorders, wound healing or neoplastic tissue transformation. The

functional significance of the accumulation of mast cells in these processes is largely

unknown. It is now established that bone marrow-derived mast cell progenitors

circulate in peripheral blood and subsequently migrate into the tissue where they

undergo final maturation under the influence of local microenvironmental factors.

Cytokines are of particular importance for mast cell recruitment, development, and

function. Stem cell factor (SCF) is a unique mast cell growth factor, since mast cells

disappear completely in the absence of SCF. However, several other cytokines such

as IL-3 and IL-4 have been shown to influence mast cell proliferation and function

also. This review focuses on the role of cytokines in the regulation of mast cell

hyperplasia.

Allergy and Immunology, Vol. 127, No. 2, 2002

Ultrastructural Changes in the Cerebral Artery Wall Induced by Long-Term Sympathetic Denervation

UThis study was performed to determine to what extent the morphology of the rabbit middle cerebral artery is affected by the absence of the sympathetic nervous system. Six weeks after unilateral ablation of the superior cervical ganglion, which induced ipsilateral degeneration and disappearance of the perivascular noradrenergic nerve fibers, comparison between the ipsi- and the contralateral middle cerebral arteries revealed that the denervated arterial wall underwent significant thickening. This thickening was principally due to hypertrophy of the smooth muscle cells (SMC), together with an increase in the amount of medial and adventitial collagen. The hypertrophied SMC showed important morphological and ultrastructural modifications – irregular shape, increase in the number of organdies (particularly of Golgi apparatus, free ribosomes, rough endoplasmic reticulum and microtubules), large indented nuclei rich in euchromatin – indicating profound changes in their metabolic and contractile activity which could result in an alteration of their mechanical properties. As these alterations were strictly ipsilateral to the sympathectomy it is likely that they are the direct consequence of the suppression of a regulatory ‘trophic’ factor linked to the presence of sympathetic nerve fibers. This concept is reinforced by the fact that the first SMC affected are those situated at the media/adventitial border, in the vicinity of adventitial nerve bundles. Thus, the sympathetic nervous system appears to play a key role in the long-term regulation of the cerebral vascular tree structure.

Copyright © 1988 S. Karger AG, Basel

http://content.karger.com/ProdukteDB/produkte.asp?Doi=158727

Sympathectomy induces novel purinergic sensitivity in A afferents from sciatic nerve

It is thought that this novel purinergic sensitivity may contribute to neuropathic paraesthesia and pain.

CHEN YONG, ZHANG YI-HONG, BIE BI-HUA, ZHAO ZHI-QI

Shanghai Institute of Physiology, Chinese Academy of Sciences

Acta Pharmacol Sin, 2000 Nov; 21 (11):1002-1004

The nerve endings in Schwann cells under the endothelium degenerated after sympathectomy

ep.physoc.org/content/52/1/31.full.pdf

patients with brain stem lesions and patients after sympathectomy have reduced or absent skin wrinkling on the affected side

Biomedecine & Pharmacotherapy Volume 55, Issue 8, October 2001, Pages 475-478