Defining cutaneous autonomic denervation in central neurodegenerative disorders
Final Report Abstract
Cutaneous autonomic function can be quantified by the assessment of sudomotor and vasomotor responses. Although piloarrector muscles are innervated by the sympathetic nervous system, there are, at present, no methods to quantify pilomotor function. This research project aimed to develop a test to quantify pilomotor function in humans. Fifteen healthy male volunteers aged 24-40 years participated in 3 studies. Piloerection was stimulated by iontophoresis of 1% phenylephrine. Silicon impressions of goose bumps were quantified by size, number and area. In study 1, the direct and indirect response to phenylephrine iontophoresis on both forearms was compared. In study 2, subjects were randomized to receive 2% lidocaine (to block the axon-reflex) or placebo. In study 3, subjects were treated with iontophoresis of normal saline alone. Iontophoresis of phenylephrine induced piloerection in both the direct and axon-reflex mediated regions. Piloarrector function in the right and left arms was similar. Pretreatment with lidocaine resulted in decreased numbers of impressions in the indirect area (57.2±13.4 control vs. 35.4±11.9 lidocaine; p<0.001). The area of axon-reflex mediated piloerection was attenuated after lidocaine application (37.9±15.6 cm2 vs. 22.9±7.4 cm2, p<0.01). Iontophoresis of saline alone did not result in piloerection. In conclusion, phenylephrine provokes piloerection directly and indirectly through an axon-reflex mediated response that is attenuated by lidocaine. The quantitative pilomotor axon-reflex test (QPART) may complement other measures of cutaneous autonomic nerve fiber function.
Publications
- Hypogonadism and Erectile Dysfunction Associated With Soy Product Consumption. Nutrition. 2011;27:859-62
Siepmann T, Roofeh J, Kiefer FW, Edelson DG
