Many injuries to the nervous system are followed by incomplete recovery or even increasing disability over time. Some of these long term effects are due to the loss of access to growth factors called neurotrophins that provide essential support for adult nerve cells. We recently discovered that immune responses can be triggered by injury leading to inflammation around the damaged nerve cells. Control of inflammation may therefore allow the remaining nerve cells to survive until treatments that enable them to regenerate can be developed.
http://www.neura.edu.au/health/nerve-and-spinal-cord-injury
Saturday, April 30, 2011
Friday, April 29, 2011
bilateral sympathectomy results in marked reduction in concentration of myocardial catecholamines - this affects contractility
Science 10 April 1959: Vol. 129. no. 3354, pp. 967 - 968 DOI: 10.1126/science.129.3354.967 |
1 Department of Pharmacology and Toxicology, University of Wisconsin, Madison
In cats bilateral sympathectomy or administration of reserpine results in a marked reduction in concentration of myocardial catecholamines. The contractility of papillary muscles from such animals is significantly less than that of muscles from untreated animals. These findings demonstrate the importance of normal levels of myocardial catecholamines in the maintenance of normal cardiac contractility.
Wednesday, April 27, 2011
Successful lawyer died after procedure to cure blushing
ALAN Synnott was the country's leading solicitor specialising in personal injuries.
He had built up a large and very successful practice, but the 44-year-old father of three suffered from social phobia and facial blushing.
The blushing was interfering with his ability to speak in public and to run his office and deal with staff.
He was referred to a surgeon for an operation to stop the blushing but, during the operation, a vein and artery were damaged and massive bleeding occurred.
Emergency surgery had to be carried out and Mr Synnott, according to court papers, lost over three times his total blood volume in a 3½-hour period.
Three days later, after brain scans, he was pronounced dead.
Yesterday his grieving widow, Eleanor Synnott, settled her action for damages for €5m. "This has given me closure but no money is going to compensate me for the enormous loss of my wonderful husband and father of my children," Mrs Synnott said outside the Four Courts.
She had sued Austin Leahy, a surgeon attached to the Bon Secours Hospital, Glasnevin, Dublin, who carried out the operation over two years ago.
http://www.independent.ie/national-news/5m-payout-to-family-after-fatal-operation-223707.html
Tuesday, April 26, 2011
No significant change in tissue blood flow after sympathectomy
Lumbar sympathectomy is widely used in the treatment of peripheral vascular disease involving the lower extremity. The obvious increase in skin temperature postoperatively has led to the belief that there is a concommitant increase in perfusion of all tissues in the leg.
Recent evidence suggests that this increase in total blood flow represents, in the main, arteriovenous shunting with a little, if any effect on the nutritive blood flow at the tissue level. Studies aimed at investigating the effect of lumbar sympathectomy on regional tissue circulation have utilized the local clearance of radioactive isotopes. No significant change in the clearance of these substances in muscle have been noted following lumbar sympathectomy in man.
Tissue Blood Flow in the Canine Lower Limb Following Lumbar SympathectomyVASC ENDOVASCULAR SURG November 1972 6: 227-238,
increased blood supply is associated with decreased vascular permeability
The influence of the sympathetic nervous system on capillary permeability was studied in cats. The dye penetration from the blood through the synovial membrane was tested by perfusing the two knee joints, one of which was deprived of its sympathetic nerve supply by unilateral lumbosacral
sympathectomy.
In confirmation of previous experiments, it was found in a great majority of experiments that, in spite of marked vasodilatation, the dye excretion was considerably reduced on the sympathectomised side.
A permeability factor under the influence of the sympathetic nervous system has been postulated; its character and mechanism is still unknown.
Further unpublished experiments seem to support the view that increased blood supply is associated with decreased vascular permeability.
Res Exp Med (Berl) 173, 1--8 (1978)
sympathectomy.
In confirmation of previous experiments, it was found in a great majority of experiments that, in spite of marked vasodilatation, the dye excretion was considerably reduced on the sympathectomised side.
A permeability factor under the influence of the sympathetic nervous system has been postulated; its character and mechanism is still unknown.
Further unpublished experiments seem to support the view that increased blood supply is associated with decreased vascular permeability.
Res Exp Med (Berl) 173, 1--8 (1978)
Sunday, April 24, 2011
The effect of cervical sympathectomy on retinal vessel responses to systemic autonomic stimulation
The retinal vessel calibre responses to systemic sympathetic stimulation, were studied in nine patients (eight male; mean age: 31.7 years; range: 19-58 years) with unilateral disruption of their cervical sympathetic tract. All patients had ipsilateral decreased/absent facial sweating and a Horners syndrome, evidence of unilateral sympathetic denervation. Both eyes of each patient were studied and the results were analysed in two groups: the group of nine sympathectomised eyes and the control group of unaffected fellow eyes. During handgrip contraction there was a significant difference in the mean retinal arteriolar constriction (mean +/- SEM) between the group of sympathectomised eyes (4.6 +/- 0.89%) and control eyes (7.1 +/- 1.13%), p less than 0.01. Similarly, there was a significant difference in mean venule constriction during sustained handgrip contraction between the group of sympathectomised eyes (1.5 +/- 0.67%) and control eyes (4.9 +/- 0.98%), p less than 0.05. There was no significant difference in the mean rise in diastolic blood pressure between the two groups: control eyes +27.9 +/- 2.38 mmHg and sympathectomised eyes +27.8 +/- 2.25 mmHg. There was no correlation between the blood pressure and retinal vessel responses in either group. These results suggest that the sympathetic nervous system plays an integral role in retinal blood flow regulation.
http://www.ncbi.nlm.nih.gov/pubmed/2323469
http://www.ncbi.nlm.nih.gov/pubmed/2323469
Inflammation after a spinal cord injury (SCI) is nonresolving
Inflammation after a spinal cord injury (SCI) is nonresolving, and can be characterized by quantification of lymphocytes using resolution indexes (Ri) and resolution plateaus (Rp), according to an experimental study published online March 22 in Brain Pathology.
Harald Prüss, M.D.,
http://www.mdnews.com/news/hd/2011_16/hd_651416
Harald Prüss, M.D.,
http://www.mdnews.com/news/hd/2011_16/hd_651416
Saturday, April 23, 2011
It is possible that sympathectomy affects non-immunological processes involved in tumor progression, such as extravasation, development of blood supply
Lacrimal gland, tear film, and dry eye syndromes 2:
basic science and clinical relevanceSpringer, 1998 - Medical - 1051 pages
GUSTATORY SWEATING AND OTHER RESPONSES AFTER SYMPATHECTOMY
Gustatory sweating on the head, neck and arms, often occurs after cervico-thoracic sympathectomy. Haxton (1948) reported an incidence of 36 percent, the same as in the present series. It was thought that some information about regeneration in the cervical sympathetic might be revealed by investigation of this surgical curiosity.
Although sweating is the common gustatory response after cervical sympathectomy, other changes are experienced. Haxton (1948) described associated paresthesia and flushing, gooseflesh may occur (Herxheimer, 1958) and vaso-constriction is reported in this paper. These occur together or separately and occasionally sweating might be absent. The subject has been confused by comparison with post-parotidectomy gustatory sweating which has a different mechanism (Glaister et al.,1958; Bloor, 1958).
Sweating is produced by cholinergic sympathetic fibres. In normal individuals both vasocontriction and gooseflesh are adrenergic. This also holds in gustatory responses. Figure 2 shows blocking of sweating by atropine, whilst gooseflesh continues unchanged.
The tingling sensations were described as being unlike normal sensation, and likened to plucking out of hair. In one patient in was so unpleasant that she refused to take a test stimulus. Flushing usually occurs on the upper chest and neck, and is an erythema with sharp demarcation, not associated with a rise in skin temperature.
Of the patients, 29 were found to have gustatory responses, and 24 were studied in detail. Of 22 patients with sweating who could be studied, 11 had gooseflesh, 10 tingling, 6 flushing, and 4 vasoconstriction. Four patients, however, had no sweating and their gustator responses consisted of gooseflesh and tingling in one, tingling alone, and flushing in two. None of these four showed vasoconstriction.
The stimulus for testing used was usually Worcester sauce, but specificity of the response was sometimes great, and one patient reacted only to boiled sweets made by one particular firm.
Sweating is produced by cholinergic sympathetic fibres. In normal individuals both vasocontriction and gooseflesh are adrenergic. This also holds in gustatory responses. Figure 2 shows blocking of sweating by atropine, whilst gooseflesh continues unchanged.
The tingling sensations were described as being unlike normal sensation, and likened to plucking out of hair. In one patient in was so unpleasant that she refused to take a test stimulus. Flushing usually occurs on the upper chest and neck, and is an erythema with sharp demarcation, not associated with a rise in skin temperature.
Of the patients, 29 were found to have gustatory responses, and 24 were studied in detail. Of 22 patients with sweating who could be studied, 11 had gooseflesh, 10 tingling, 6 flushing, and 4 vasoconstriction. Four patients, however, had no sweating and their gustator responses consisted of gooseflesh and tingling in one, tingling alone, and flushing in two. None of these four showed vasoconstriction.
The stimulus for testing used was usually Worcester sauce, but specificity of the response was sometimes great, and one patient reacted only to boiled sweets made by one particular firm.
http://brain.oxfordjournals.org/content/92/1/137.extract &
http://ang.sagepub.com/content/17/3/143.extract
The development of gustatory sweating after cervical sympathectomy can only be explained if one is to admit that the primary event of gustatory sweating is a degeneration of the cervical sympathetic neurons. The initial event is the loss of postganglionic sympathetic neurons and the resulting denervation of the corresponding facial sweat glands. Regeneration of parasympathetic fibers, within the degenerating sympathetic neurilemmal sheets, is a secondary event although it accounts for the observed symptoms.
http://ang.sagepub.com/content/17/3/143.extract
The development of gustatory sweating after cervical sympathectomy can only be explained if one is to admit that the primary event of gustatory sweating is a degeneration of the cervical sympathetic neurons. The initial event is the loss of postganglionic sympathetic neurons and the resulting denervation of the corresponding facial sweat glands. Regeneration of parasympathetic fibers, within the degenerating sympathetic neurilemmal sheets, is a secondary event although it accounts for the observed symptoms.
Salivary gland disorders
Mechanism of adrenal cortex stimulation following cervical sympathectomy
http://www.ncbi.nlm.nih.gov/pubmed/14022522
Effects of right cervical sympathectomy on the ascorbic acid content of adrenals of thyroidectomized female rats
http://www.ncbi.nlm.nih.gov/pubmed/5358480
Consequences of right cervical sympathectomy on thyroid and adrenals in castrated rats
http://www.ncbi.nlm.nih.gov/pubmed/5734998
cervical sympathectomy works systemically through hypothalamus endocrine system
Background: To investigate the general action of stellate ganglion block (SGB), we examined the effects of heat stimulation and cold stress on the behavior and stress hormone of the bilateral cervical sympathectomy rats as a long-term and repeated SGB model. Methods: Wistar's male rats were divided into three groups: control (C), sham operation (S) and sympathectomy (Sx) groups. After 2 weeks, two experiments were done. One was measurement of escape response time from the heat stimulus and the other was hormone measurement. Serum adreno-corticotropic hormone (ACTH), .ALPHA.-melanocyte stimulating hormone (.ALPHA.-MSH) and .BETA.-endorphine (.BETA.-END) levels were measured assigning 3 groups to 2 subgroups with and without cold stress. Results: Escape response time was significantly extended in the Sx group. ACTH in the Sx group was significantly higher than in other groups, but changes of ACTH by cold stress were similar in 3 groups. In the Sx group .ALPHA.-MSH was hardly changed by cold stress while .ALPHA.-MSH was significantly decreased in the S group. Changes of .BETA.-END by cold stress were similar in the S and Sx groups. Conclusions: These results suggest that SGB works systemically through hypothalamus endocrine system and affects stress hormone differently. (author abst.)
http://sciencelinks.jp/j-east/article/200402/000020040204A0020288.php
Unilateral cervical sympathectomy resulted in a moderate and short decrease in milk secretion
the average amount of milk given by operated animals 10 days after operation being 76-3% of the initial level. Total cervical sympathectomy (the 2nd operation was performed 1 month later) caused a much greater and more prolonged decrease in milk secretion, 59.7% of the initial level being secreted during the 10 days after operation. A gradual increase in milk secretion was observed after the operation and this increase was more gradual after total sympathectomy than after partial sympathectomy. Denervation of the thyroid and parathyroids did not decrease milk secretion. Section of the pituitary stalk in 6 goats, which included complete section (2 goats), complete section with scar tissue at the site of section and considerable damage to the median eminence of the tuber einereum (1 goat) and incomplete section (3 goats) was performed. Milk ejection disappeared completely for 7-11 days in the goats with complete section and remained defective for some weeks after, but was still effective in those where the infundibular stem and part of the glandular portion of the pituitary stalk was still intact. Milk secretion was 28.9% of the initial level in the goats with complete section and 12.9% in the goat with the scar tissue whereas it was 40.5 and 55.7% in the incompletely sectioned and control operated goats. (See also D.S.A. 21 [3081].) D.E.E.
Monday, April 18, 2011
adult neurogenesis may contribute to the functioning, and phyio- and pathology of the CNS, particularly to the etiology of neurological diseases and disorders
Neuroinflammation is a process in which the brain responds to infections, diseases and injuries [1, 2]. Neuroinflammation involve two types of immune cells: lymphocytes, monocytes and macrophages of the hematopoietic system, and microglial cells of the CNS [3, 4]. Neuroinflammation disrupts the blood-brain barrier (BBB), allowing cells from the hematopoietic system to leave the blood stream and come in contact to the injury site [5]. The immune cells respond to injuries by eliminating debris and, synthesizing and releasing a host of powerful regulatory substances, like the complements, cytokines, chemokines, glutamate, interleukins, nitric oxide, reactive oxygen species and transforming growth factors [6-10]. The substances have both beneficial and harmful effects on the cellular environment, creating further damages [11] (fig. 1). Mature astrocytes are also activated following injury to the CNS [12, 13].
Chronic inflammation during depressive episodes could predispose depressive patients to neurodegenerative diseases, later in life [29].
http://www.medsci.org/v05p0127.htm
Chronic inflammation during depressive episodes could predispose depressive patients to neurodegenerative diseases, later in life [29].
http://www.medsci.org/v05p0127.htm
The cerebral vessels became hypersensitive to epinephrine after cervical sympathectomy
The cerebral vessels became hypersensitive to epinephrine after cervical sympathectomy.
HERTZMAN, A. B., AND DILLON, J. B.
Annual Review of Physiology
Vol. 4: 187-214 (Volume publication date March 1942)
HERTZMAN, A. B., AND DILLON, J. B.
Annual Review of Physiology
Vol. 4: 187-214 (Volume publication date March 1942)
Post-sympathectomy neuralgia is proposed here to be a complex neuropathic and central deafferentation/reafferentation syndrome
http://www.ncbi.nlm.nih.gov/pubmed/8867242
Friday, April 15, 2011
Wednesday, April 6, 2011
Nerve regeneration commonly occurs following both surgical or chemical ablation
This systematic review found only one small study (20 participants) of good methodological quality, which reported no significant difference between surgical and chemical sympathectomy for relieving neuropathic pain. Potentially serious complications of sympathectomy are well documented in the literature, and one (neuralgia) occurred in this study.
The practice of sympathectomy for treating neuropathic pain is based on very weak evidence. Furthermore, complications of the procedure may be significant.
http://www2.cochrane.org/reviews/en/ab002918.html
This is a Cochrane review abstract and plain language summary, prepared and maintained by The Cochrane Collaboration, currently published in The Cochrane Database of Systematic Reviews 2011 Issue 3, Copyright © 2011 The Cochrane Collaboration. Published by John Wiley and Sons, Ltd.. The full text of the review is available inThe Cochrane Library (ISSN 1464-780X).
Tuesday, April 5, 2011
Decreased brain metabolism, rather than an increased intracranial pressure, is the cause of decreased cerebral blood flow after superior cervical sympathetic ganglionectomy
"The reduced brain metabolism and consequently reduced cerebral perfusion in the late
postsympathectomy period could account for reduction in CSF production (Bering3)."
"In support of the above statement we mention that on the late postsympathectomy (11 to 24 months) group of dogs besides the lowered CBF
(31.36 ml/100 gm brain weight/minute) and MCP (79.3 mm NS) also a lowered MVP (46.5 mm NS) was found. These data indicate that cervicalsympathectomy has a profound and intricate effect on the dynamics of cerebrovascular fluids and probably, in the background of all observedphenomena, a decreased cerebral metabolism as a sympathectomy effect is the underlying cause. Correspondingly the cerebral metabolic rate ofoxygen (CMR O2) decreased to 2.94 and 2.43 ml of O2/IOO gm brain weight/ minute in the sympathectomized groups."
"Decreased brain metabolism, rather than an increased intracranial pressure, is the cause of decreased cerebral blood flow after superior
cervical sympathetic ganglionectomy."
http://archsurg.ama-assn.org/cgi/content/summary/90/3/418
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