title: The pattern and time course of somatosensory changes in the human UVB sunburn model reveal the presence of peripheral and central sensitization.
abstract: The ultraviolet B (UVB) sunburn model was characterized with a comprehensive battery of quantitative sensory testing (QST). Primary hyperalgesia in UVB-irradiated skin and secondary hyperalgesia in adjacent nonirradiated skin were studied in 22 healthy subjects 24h after irradiation with UVB at 3-fold minimal erythema dose of a skin area 5 cm in diameter at the thigh and compared to mirror-image contralateral control areas. The time course of hyperalgesia over 96 h was studied in a subgroup of 12 subjects. Within the sunburn area, cold hyperesthesia (P=.01), profound generalized hyperalgesia to heat (P<.001), cold (P<.05), pinprick and pressure (P<.001), and mild dynamic mechanical allodynia (P<.001) were present. The finding of cold hyperalgesia and cold hyperesthesia is new in this model. The sunburn was surrounded by large areas of pinprick hyperalgesia (mean±SEM, 218±32 cm(2)) and a small rim of dynamic mechanical allodynia but no other sensory changes. Although of smaller magnitude, secondary hyperalgesia and dynamic mechanical allodynia adjacent to the UVB-irradiated area were statistically highly significant. Primary and secondary hyperalgesia developed in parallel within hours, peaked after 24-32 h, and lasted for more than 96 h. These data reveal that the UVB sunburn model activates a broad spectrum of peripheral and central sensitization mechanisms and hence is a useful human surrogate model to be used as a screening tool for target engagement in phases 1 and 2a of drug development.
authors: Vienna Human Pain Research Group, Department of Anaesthesia, General Intensive Care Medicine and Pain Control, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria Vienna Human Pain Research Group, Department of Neurology, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria Department of Neurology, University Hospital, Johannes Gutenberg-University, Langenbeckstrasse 1, D-55099 Mainz, Germany Department of Palliative Medicine, University Hospital Bonn, Sigmund-Freud-Str. 25, D-53127 Bonn, Germany Department of Neurophysiology, Center of Biomedicine and Medical Technology Mannheim (CBTM), Medical Faculty Mannheim, Ruprecht-Karls-University Heidelberg, Ludolf-Krehl-Strasse 13-17, D-68167 Mannheim, Germany.
authors: Burkhard
authors: B
authors: Gustorff
authors: Thomas
authors: T
authors: Sycha
authors: Doris
authors: D
authors: Lieba-Samal
authors: Roman
authors: R
authors: Rolke
authors: Rolf-Detlef
authors: RD
authors: Treede
authors: Walter
authors: W
authors: Magerl
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D059333:Central Nervous System Sensitization / Q000502:physiology*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D006930:Hyperalgesia / Q000209:etiology*; D017078:Laser-Doppler Flowmetry; D008297:Male; D009434:Neural Pathways / Q000502:physiology; D010147:Pain Measurement; D017288:Pain Threshold / Q000502:physiology*; D010812:Physical Stimulation / Q000009:adverse effects; D011601:Psychophysics; D012867:Skin / Q000098:blood supply; D013471:Sunburn / Q000150:complications* / Q000209:etiology; D013997:Time Factors; D014466:Ultraviolet Rays / Q000009:adverse effects; D014732:Vibration; D055815:Young Adult