Functional attributes discriminating mechano-insensitive and mechano-responsive C nociceptors in human skin.
نویسندگان
چکیده
Microneurography was used in healthy human subjects to record action potentials from unmyelinated nerve fibers (C units) in cutaneous fascicles of the peroneal nerve. Activity-dependent slowing (n = 96) and transcutaneous electrical thresholds (n = 67) were determined. Eight units were sympathetic efferents according to their responses to sympathetic reflex provocations. Mechano-heat-responsive C units (CMH) (n = 56) had thresholds to von Frey hair stimulation 35 mA for CH and CM(i)H(i) units. Activity-dependent slowing was much more pronounced in mechano-insensitive than in mechano-responsive units, without overlap. Sympathetic efferent C units showed intermediate slowing, significantly different from CMH, and completely separate from CH and CM(i)H(i) units. The activity-dependent slowing of conduction provides evidence for different membrane attributes of different classes of C fibers in humans.
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ورودعنوان ژورنال:
- The Journal of neuroscience : the official journal of the Society for Neuroscience
دوره 19 22 شماره
صفحات -
تاریخ انتشار 1999