Sympathetic denervation is frequently observed in heart disease. To investigate the linkage of sympathetic denervation and cardiac arrhythmia, we developed a rat model of chemical sympathectomy by subcutaneous injections of 6-hydroxydopamine (6-OHDA).
We observed that sympathectomy (i) decreased cardiac sympathetic nerve density and norepinephrine level, (ii) reduced the protein expression of Kv4.2, Kv1.4, and Kv channel-interacting protein 2 (KChIP2), (iii) decreased current densities and delayed activation of Ito channels, (iv) reduced the phosphorylation of extracellular signal-regulated kinase 1 and 2 (ERK1/2) and cAMP response element-binding protein (CREB), and (v) increased the severity of ventricular fibrillation induced by rapid pacing.
We conclude that chemical sympathectomy downregulates the expression of selective Kv channel subunits and decreases myocardial Ito channel activities, contributing to the elevated susceptibility to ventricular fibrillation.
Can. J. Physiol. Pharmacol. 86(10): 700–709 (2008)
"Sympathectomy is a technique about which we have limited knowledge, applied to disorders about which we have little understanding." Associate Professor Robert Boas, Faculty of Pain Medicine of the Australasian College of Anaesthetists and the Royal College of Anaesthetists, The Journal of Pain, Vol 1, No 4 (Winter), 2000: pp 258-260
The amount of compensatory sweating depends on the patient, the damage that the white rami communicans incurs, and the amount of cell body reorganization in the spinal cord after surgery.
Other potential complications include inadequate resection of the ganglia, gustatory sweating, pneumothorax, cardiac dysfunction, post-operative pain, and finally Horner’s syndrome secondary to resection of the stellate ganglion.
www.ubcmj.com/pdf/ubcmj_2_1_2010_24-29.pdf
After severing the cervical sympathetic trunk, the cells of the cervical sympathetic ganglion undergo transneuronic degeneration
After severing the sympathetic trunk, the cells of its origin undergo complete disintegration within a year.
http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0442.1967.tb00255.x/abstract
Other potential complications include inadequate resection of the ganglia, gustatory sweating, pneumothorax, cardiac dysfunction, post-operative pain, and finally Horner’s syndrome secondary to resection of the stellate ganglion.
www.ubcmj.com/pdf/ubcmj_2_1_2010_24-29.pdf
After severing the cervical sympathetic trunk, the cells of the cervical sympathetic ganglion undergo transneuronic degeneration
After severing the sympathetic trunk, the cells of its origin undergo complete disintegration within a year.
http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0442.1967.tb00255.x/abstract
Sunday, July 26, 2009
Sterility following lumbar sympathectomy
Bacq (1931) found that bilateral lumbar sympathectomy in rabbits resulted in sterility with prolonged copulation and absence of orgasm.
J. Reprod. Fertil. (1964) 7, 113-122
J. Reprod. Fertil. (1964) 7, 113-122
Altered Cerebral Blood Flow following Sympathectomy
The subject has recently been studied by James, Millar&Purves who measured the cerebral vascular response to hypoxia with all nerves intact and following division or stimulation of the vagus and cervical sympathetic nerves. The effect of sympathectomy (...) is seen to consist of an elevation of both grey and white matter blood flow 40-50 per cent above control over the range of PaO2 tested, 35 to 440 mmHg. When the cervical sympathetic nerve as stimulated at constant frequency and intensity, cortical flow was reduced to control levels.
The Physiology of the Cerebral Circulation (Monographs of the Physiological Society) by M. J. Purves (Hardcover - May 31, 1972)
The Physiology of the Cerebral Circulation (Monographs of the Physiological Society) by M. J. Purves (Hardcover - May 31, 1972)
decrease in resting pulmonary resistance that follows thoracic thoracic sympathectomy
Diminished sympathetic constrictor discharge to pulmonary arterioles probably contributes to the lowering of resistance. No direct evidence for such an action has been presented, but the decrease in resting pulmonary resistance that follows thoracic thoracic sympathectomy shows that the potential for such a response exists. Whatever the mechanism, the net result is that pulmonary blood flow can be increased greatly without raising intravascular pressures to a degree that would encourage capillary transudation of fluid.
Cardiovascular physiology
By William R. MilnorNew York : Oxford University Press, 1990. |
Sympathetic nervous system control of anti-influenza CD8+ T cell responses
Adoptive transfer experiments indicate that enhanced CD8+ responses do not result from permanent alterations in CD8+ T cell function in sympathectomized mice. Rather, additional findings suggest that the sympathetic nervous system tempers the capacity of antigen-presenting cells to activate naïve CD8+ T cells. We also show that antiviral CD8+ T cell responses are enhanced by administration of a β2 (but not β1 or α) adrenergic antagonist. These findings demonstrate a critical role for the sympathetic nervous system in limiting CD8+ T cell responses and indicate that CD8+ T cell responses may be altered in patients using β-blockers, one of the most widely prescribed classes of drugs.
PNAS March 31, 2009 vol. 106 no. 13
PNAS March 31, 2009 vol. 106 no. 13
Following sympathectomy the basal t-PA activity in plasma was 70% less than controls
Following sympathectomy: (i) the basal t-PA activity in plasma was 70% less than controls (2.92 ± 1.96 versus 9.33 ± 1.72 IU/ml;P ≤ 0.001); (ii) the acute release from isolated vessels induced by bradykinin or phenylephrine was comparably reduced; and (iii) the greatest reductions occurred in densely innervated small vessel explants. The results provide new support for an autonomic regulation of neural t-PA release into the vessel wall matrix and blood of densely innervated thin-walled microvessels.
Blood Coagulation & Fibrinolysis:
September 2002 - Volume 13 - Issue 6 - pp 471-481
In another work on dogs, sympathectomy caused a state similar to atrophic rhinitis in man
Relationship Between the Vegetative Innervation and the Sensibility of the Nasal Mucosa
Z. Krajina; Z. Poljak
Acta Oto-Laryngologica, 1651-2251, Volume 79, Issue 3, 1975, Pages 172 – 175
Z. Krajina; Z. Poljak
Acta Oto-Laryngologica, 1651-2251, Volume 79, Issue 3, 1975, Pages 172 – 175
Structural changes associated with parotid "degeneration secretion" after post-ganglionic sympathectomy
This loss of granules is considered to be due to sympathetic "degeneration secretion" caused by the release of noradrenaline from the degenerating adrenergic nerves between 12 and 24 hours after ganglionectomy. This is thought to be the first example of morphological change resulting from "degeneration activation" to be recorded microscopically.
Cell Tissue Res. 1975 Sep 16;162(1):1-12.
Cell Tissue Res. 1975 Sep 16;162(1):1-12.
PMID: 1175216 [PubMed - indexed for MEDLINE]
acinar degranulation following sympathectomy
Chronic bilateral postganglionic sympathectomy (4-6 weeks duration) caused a drastic reduction in the capacity of the gland to secrete saliva in response to parasympathetic stimulation, reaching only one-third of that from normal animals. The initial output of amylase was greater than in normal animals but the total output was similar. The control unstimulated sympathectomized glands appeared similar morphologically to normal resting glands. However, on the parasympathetically stimulated side, besides the usual amount of acinar degranulation, there was also a conspicuous development of acinar vacuolation, not seen in the other groups of animals.
J. Physiol. November 15, 2008 586:5537-5547
J. Physiol. November 15, 2008 586:5537-5547
Cervical sympathectomy inhibits axonal transport of gonadotropin-releasing hormone
To examine the effects of cervical sympathectomy on the transport of gonadotropin-releasing hormone (GnRH) between the hypothalamic neurons and the median eminence, 16 male rats were assigned into four groups: control (C), light (L), light-sympathectomy (LS), and light-colchicine (LC).
Considering the action of colchicine, which inhibits axonal transport, it is suggested that cervical sympathectomy also inhibits axonal transports of GnRH between the GnRH neurons and the median eminence during continuous exposure to light.
Journal of Anesthesia
Volume 10, Number 3 / September, 1996
Considering the action of colchicine, which inhibits axonal transport, it is suggested that cervical sympathectomy also inhibits axonal transports of GnRH between the GnRH neurons and the median eminence during continuous exposure to light.
Journal of Anesthesia
Volume 10, Number 3 / September, 1996
Calcitonin gene-related peptide and substance P contribute to reduced blood pressure in sympathectomized rats
Am J Physiol Heart Circ Physiol 289: H1169-H1175, 2005.
Sympathectomized rats displayed reductions in blood pressure (BP) and atria norepinephrine levels, whereas NGF levels in the DRG, spleen, and ventricles were increased. Sympathectomy also enhanced CGRP and SP mRNA and peptide content in DRG. Administration of CGRP and SP receptor antagonists increased the BP in sympathectomized rats but not in the controls. Thus sympathectomy enhances sensory neuron CGRP and SP expression that contributes to the BP reduction.
Sympathectomized rats displayed reductions in blood pressure (BP) and atria norepinephrine levels, whereas NGF levels in the DRG, spleen, and ventricles were increased. Sympathectomy also enhanced CGRP and SP mRNA and peptide content in DRG. Administration of CGRP and SP receptor antagonists increased the BP in sympathectomized rats but not in the controls. Thus sympathectomy enhances sensory neuron CGRP and SP expression that contributes to the BP reduction.
Neurogenic and non-neurogenic inflammation in the rat paw following chemical sympathectomy
http://www.ncbi.nlm.nih.gov/pubmed/1723182?dopt=Abstract
Neuroscience. 1991;45(3):761-5.
Neonatal guanethidine sympathectomy caused an 86% depletion of noradrenaline in the paw skin and neurogenic plasma protein extravasation upon antidromic nerve stimulation was impaired. Sensory neuropeptides were unchanged in the skin after neonatal guanethidine and only calcitonin gene-related peptide content was increased in the spinal cord and sciatic nerves. The other observations (i.e. the sensitivity towards heat stimuli, the neurogenic mustard oil inflammation and the non-neurogenic carrageenan oedema) were similar to those observed after neonatal 6-hydroxydopamine treatment.
Neuroscience. 1991;45(3):761-5.
Neonatal guanethidine sympathectomy caused an 86% depletion of noradrenaline in the paw skin and neurogenic plasma protein extravasation upon antidromic nerve stimulation was impaired. Sensory neuropeptides were unchanged in the skin after neonatal guanethidine and only calcitonin gene-related peptide content was increased in the spinal cord and sciatic nerves. The other observations (i.e. the sensitivity towards heat stimuli, the neurogenic mustard oil inflammation and the non-neurogenic carrageenan oedema) were similar to those observed after neonatal 6-hydroxydopamine treatment.
Sympathectomy exaggerates antihypertensive effect of vasopressin withdrawal
The results are consistent with the hypothesis that withdrawal of sympathetic activity is a contributing factor or a prerequisite condition for development of a WAP.(withdrawal-induced antihypertensive phenomenon)
AJP - Heart and Circulatory Physiology, Vol 268, Issue 1 1-H6, Copyright © 1995 by American Physiological Society
AJP - Heart and Circulatory Physiology, Vol 268, Issue 1 1-H6, Copyright © 1995 by American Physiological Society
plasma levels of natriuretic peptides in response to sympathectomy
The occurrence of receptor binding sites for natriuretic peptides was examined by in vitro receptor autoradiography. In contrast to the marked occurrence of natriuretic peptide receptor binding sites seen in the ventricular endocardium of control rats, the sympathectomized rats exhibited a decreased number of binding sites for natriuretic peptides in the endocardium of both the right and left chambers. Interestingly, this was found in parallel with a significant decrease of systolic and diastolic blood pressure and increased plasma levels of pro-atrial natriuretic peptide in the treated group of rats. These findings, together with those in previous studies, give support to an idea that one part of the blood pressure-decreasing effects, seen in patients treated with β-adrenergic blockade, might be through a reduction of the natriuretic clearance receptor C, then giving rise to increased levels of atrial natriuretic peptide.
http://cat.inist.fr/?aModele=afficheN&cpsidt=17030448
http://cat.inist.fr/?aModele=afficheN&cpsidt=17030448
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