Following a peripheral nerve injury, a sterile inflammation develops in sympathetic and dorsal root ganglia (DRGs) with axons that project in the damaged nerve trunk. Macrophages and T-lymphocytes invade these ganglia where they are believed to release cytokines that lead to hyperexcitability and ectopic discharge, possibly contributing to neuropathic pain. Here, we examined the role of the sympathetic innervation in the inflammation of L5 DRGs of Wistar rats following transection of the sciatic nerve, comparing the effects of specific surgical interventions 10-14days prior to the nerve lesion with those of chronic administration of adrenoceptor antagonists. Immunohistochemistry was used to define the invading immune cell populations 7days after sciatic transection. Removal of sympathetic activity in the hind limb by transecting the preganglionic input to the relevant lumbar sympathetic ganglia (ipsi- or bilateral decentralization) or by ipsilateral removal of these ganglia with degeneration of postganglionic axons (denervation), caused less DRG inflammation than occurred after a sham sympathectomy. By contrast, denervation of the lymph node draining the lesion site potentiated T-cell influx. Systemic treatment with antagonists of α1-adrenoceptors (prazosin) or β-adrenoceptors (propranolol) led to opposite but unexpected effects on infiltration of DRGs after sciatic transection. Prazosin potentiated the influx of macrophages and CD4+ T-lymphocytes whereas propranolol tended to reduce immune cell invasion. These data are hard to reconcile with many in vitro studies in which catecholamines acting mainly via β2-adrenoceptors have inhibited the activation and proliferation of immune cells following an inflammatory challenge.
Auton Neurosci. 2013 Dec 23.
http://www.ncbi.nlm.nih.gov/pubmed/24418114
"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
Saturday, February 15, 2014
Surgical sympathectomy is rarely performed and its use remains controversial
Although improved in some, persistent or recurrent symptoms were present in all patients after six months postoperatively. Increased sensitivity of digital vessels to circulating catecholamines, nerve fiber regeneration or incomplete sympathectomy have been postulated to lead to recurrence. Five patients developed Horner's syndrome postoperatively. A portion of the stellate ganglion was intentionally resected in 3 of the 5 patients.
http://www.ncbi.nlm.nih.gov/pubmed/8370999
http://www.ncbi.nlm.nih.gov/pubmed/8370999
Wednesday, February 12, 2014
Thursday, February 6, 2014
prolongation of the isometric (tension) period (TP) of the left ventricle occurred in the majority (72 per cent) of all cases after sympathectomy
The prolongation of the isometric (tension) period (TP) of the left ventricle which occurred in the majority (72 per cent) of all cases after unilateral or bilateral transthoracic sympathectomy (without or with unilateral or bilateral transthoracic splanchnicotomy) indicates a diminution of inotropic cardiac action. It can be assumed to correspond to the cholinergic (vagal) preponderance which results from a partial or complete sympathetic denervation of the heart. Reduction of the pulse pressure oc-
curred in 56 per cent of the cases, probably due to the same mechanism.
www.chestjournal.org/content/38/4/423.full.pdfby W RAAB - 1960
www.chestjournal.org/content/38/4/423.full.pdfby W RAAB - 1960
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