Invited reviewEvaluation of sudomotor function
Section snippets
Why evaluate sudomotor function?
The eccrine sweat gland is innervated by postganglionic sudomotor fibers. It plays an important role in thermoregulation. A diffuse loss of function can result in heat intolerance and excessive function, manifest as hyperhidrosis can be distressing. However, the importance of measurements of the sweat response resides in its value as an index of the severity and distribution of autonomic failure, and hence as an aid in the diagnosis of dysautonomia. For instance, the percent anhidrosis on the
Anatomy and physiology of sweating
Thermoreceptors are present in the preoptic-anterior hypothalamus area, responding to a deviation in core temperature relative to the temperature set point. However, other thermoreceptors in skin, viscera, and spinal cord are also important. Afferent impulses from these peripheral receptors travel in the spinothalamic tract afferent pathways, but also ascend as multisynaptic fiber pathways diffusely in the lateral spinal cord, to the reticular formation of the brain stem, and finally to the
QSART
The principle of the QSART can be surmised from Fig. 1. A commercial unit (QSWEAT) is essentially similar. When postganglionic sympathetic terminals are stimulated, an antidromic impulse occurs, reaches a branch point, then travels orthodromically to release acetylcholine from the nerve terminal. Acetylcholine traverses the neuroglandular junction and binds to M3 muscarinic receptors on eccrine sweat glands (Torres et al., 1991) to evoke the sweat response. Acetylcholinesterase in subcutaneous
Acknowledgements
This work was supported by grants from the NIH (NS32352, NS39722, and MO1 RR00585).
References (74)
- et al.
Immunohistochemical, morphological and functional changes in the peripheral sudomotor neuro-effector system in elderly people
J Auton Nerv Syst
(1992) - et al.
Sympathetic skin response: a decade later
J Neurol Sci
(1995) - et al.
Sympathetic skin response in diabetic neuropathy: a prospective clinical and neurophysiological trial on 100 patients
J Neurol Sci
(1996) - et al.
The sympathetic skin response in reflex sympathetic dystrophy
J Neurol Sci
(1995) - et al.
Thermoregulatory sweating abnormalities in diabetes mellitus
Mayo Clin Proc
(1989) - et al.
Peripheral autonomic surface potential. A quantitative technique for recording sympathetic conduction in man
J Neurol Sci
(1985) Composite autonomic scoring scale for laboratory quantification of generalized autonomic failure
Mayo Clin Proc
(1993)- et al.
Regional and individual variations in the function of the human eccrine sweat gland
J Invest Dermatol
(1970) - et al.
Characterization of muscarinic receptor subtype of rat eccrine sweat gland by autoradiography
Brain Res
(1991) - et al.
Post-stroke autonomic nervous system function: palmar sympathetic skin responses thirty or more days after cerebrovascular accident
Arch Phys Med Rehabil
(1995)