Cutaneous noradrenaline measured by microdialysis in complex regional pain syndrome during whole-body cooling and heating.
Complex regional pain syndrome (CRPS) is characterised by autonomic, sensory, and motor disturbances. The underlying mechanisms of the autonomic changes in CPRS are unknown. However, it has been postulated that sympathetic inhibition in the acute phase with locally reduced levels of noradrenaline is followed by an up-regulation of alpha-adrenoceptors in chronic CRPS leading to denervation supersensitivity to catecholamines. This exploratory study examined the effect of cutaneous sympathetic activation and inhibition on cutaneous noradrenaline release, vascular reactivity, and pain in CRPS patients and in healthy volunteers. Seven patients and nine controls completed whole-body cooling (sympathetic activation) and heating (sympathetic inhibition) induced by a whole-body thermal suit with simultaneous measurement of the skin temperature, skin blood flow, and release of dermal noradrenaline. CRPS pain and the perceived skin temperature were measured every 5 min during thermal exposure, while noradrenaline was determined from cutaneous microdialysate collected every 20 min throughout the study period. Cooling induced peripheral sympathetic activation in patients and controls with significant increases in dermal noradrenaline, vasoconstriction, and reduction in skin temperature. The main findings were that the noradrenaline response did not differ between patients and controls or between the CRPS hand and the contralateral unaffected hand, suggesting that the evoked noradrenaline release from the cutaneous sympathetic postganglionic fibres is preserved in chronic CRPS patients.
Danish Pain Research Center and Department of Neurology, Aarhus University Hospital, Aarhus, Denmark. a.terkelsen@dadlnet.dk
Astrid J
AJ
Terkelsen
Janne
J
Gierthmühlen
Lars J
LJ
Petersen
Lone
L
Knudsen
Niels J
NJ
Christensen
Jan
J
Kehr
Takashi
T
Yoshitake
Caspar S
CS
Madsen
Gunnar
G
Wasner
Ralf
R
Baron
Troels S
TS
Jensen
D000328:Adult; D003080:Cold Temperature; D020918:Complex Regional Pain Syndromes / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D007839:Functional Laterality; D006361:Heating; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000378:metabolism*; D012039:Regional Blood Flow; D012867:Skin / Q000098:blood supply / Q000294:innervation / Q000378:metabolism*; D012881:Skin Temperature; D055815:Young Adult
D009638:Norepinephrine
CRPS; Complex regional pain syndrome; LDF; Microdialysis; NE; NRS; Noradrenaline; Skin; Whole-body cooling; complex regional pain syndrome; laser Doppler flowmeter; noradrenaline; numeric rating scale