Postsympathectomy limb pain, postsympathectomy parotid pain, and Raeder's
paratrigeminal syndrome are pain states associated with the loss of sympathetic fibres
and in particular with postganglionic sympathetic lesions. There is a characteristic interval
of about 10 days between surgical sympathectomy and onset of pain. It is proposed that
this pain in man is correlated with the delayed rise in sensory neuropeptides seen in
rodents after sympathectomy. These chemical changes probably reflect the sprouting of
sensory fibres and may result from the greater availability of nerve growth factor after
sympathectomy. The balance between the sensory and sympathetic innervations of a
peripheral organ may be determined by competition for a limited supply of nerve growth
factor.
Lancet. 1985 Nov 23;2(8465):1158-60.
Saturday, October 31, 2009
Abnormal autonomic functions, however, markedly affect the individual's ability to respond to changing conditions
Normal function of all components of the ANS is not required to maintain life, as long as
environmental conditions are a constant and optimum. Abnormal autonomic functions, however,
markedly affect the individual's ability to respond to changing conditions. This can be demonstrated
by sympathectomy, the removal of sympathetic ganglia. An animal becomes highly sensitive to heat,
cold, or other forms of stress following sympathectomy. In a hot environment the animal's ability to
lose heat by increasing blood flow to the skin and by sweating is decreased. When exposed to the
cold, the animal is less able to reduce blood flow to the skin and conserve heat. Sympathectomy also
results in low blood pressure caused by dilation of peripheral blood vessels and results in the
inability to increase blood pressure during periods of physical activity.
http://www.mhhe.com/biosci/ap/seeleyap/nervous/reading3.mhtml
environmental conditions are a constant and optimum. Abnormal autonomic functions, however,
markedly affect the individual's ability to respond to changing conditions. This can be demonstrated
by sympathectomy, the removal of sympathetic ganglia. An animal becomes highly sensitive to heat,
cold, or other forms of stress following sympathectomy. In a hot environment the animal's ability to
lose heat by increasing blood flow to the skin and by sweating is decreased. When exposed to the
cold, the animal is less able to reduce blood flow to the skin and conserve heat. Sympathectomy also
results in low blood pressure caused by dilation of peripheral blood vessels and results in the
inability to increase blood pressure during periods of physical activity.
http://www.mhhe.com/biosci/ap/seeleyap/nervous/reading3.mhtml
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