Differential effects of lidocaine on nerve growth factor (NGF)-evoked heat- and mechanical hyperalgesia in humans

• Verfasst von: Weinkauf, Benjamin [VerfasserIn]
• Verfasst von: Obreja, Otilia [VerfasserIn]
• Verfasst von: Schmelz, Martin [VerfasserIn]
• Verfasst von: Rukwied, Roman [VerfasserIn]
• Titel: Differential effects of lidocaine on nerve growth factor (NGF)-evoked heat- and mechanical hyperalgesia in humans
• Verf.angabe: B. Weinkauf, O. Obreja, M. Schmelz, R. Rukwied
• E-Jahr: 2012
• Jahr: 06 March 2012
• Umfang: 7 S.
• Fussnoten: Gesehen am 07.05.2019
• Titel Quelle: Enthalten in: European journal of pain
• Ort Quelle: Malden, Mass. [u.a.] : Wiley-Blackwell, 1997
• Jahr Quelle: 2012
• Band/Heft Quelle: 16(2012), 4, Seite 543-549
• ISSN Quelle: 1532-2149
• DOI: doi:10.1016/j.ejpain.2011.08.004
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1664848800

Abstract

We investigated the effects of a non-specific sodium channel blocker (lidocaine) on heat pain thresholds and mechanical impact pain at day 7 and 21 after intradermal injection of 1 μg NGF. Measurements were performed in 12 healthy male subjects prior to and 5 min after intradermal injection of 150 μl lidocaine administered at concentrations of 0.01% (∼0.4 mM) and 0.1% (∼4 mM) to both NGF and control skin sites. NGF caused a maximum reduction of heat pain thresholds at day 7 (NGF 42.6 ± 0.6 vs. 49.4 ± 0.3 °C in control skin). Lidocaine sensitized normal skin for heat pain, but reduced heat hyperalgesia after NGF at day 7 (44.3 ± 0.8 °C, lidocaine 0.1%; p < 0.005). Pain upon supra-threshold mechanical impact stimulation was increased after NGF at day 7 (VAS 29 + 5) and massively enhanced at day 21 (VAS 64 + 5, p < 0.001). Lidocaine dose-dependently attenuated mechanically-induced pain at both control and NGF-treated sites. Maximum lidocaine effects on mechanical hyperalgesia were recorded at day 21 in NGF skin (pain reduction to VAS 37 ± 4, p < 0.00001). Repetitive impact stimuli caused increasingly more pain at the NGF sites at day 21 and this pain increase was efficiently suppressed by lidocaine 0.1%. Lidocaine differentially affects NGF-induced mechanical hyperalgesia (analgesic effect) and heat sensitivity of nociceptors (sensitizing effect). These opposing responses may be attributed to block of sodium channels vs. sensitization of TRPV1. NGF-evoked extreme mechanical impact pain indicates high action potential discharge frequencies, which might be more susceptible to lidocaine block.