Underlying mechanisms of intravenous administration of lidocaine in spinal dorsal horn

2014 Fiscal Year Final Research Report

• Project/Area Number: 25861365
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Anesthesiology
• Research Institution: Niigata University
• Principal Investigator: KURABE Miyuki 新潟大学, 医歯学総合病院, 医員 (30635579)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: リドカイン / in vivoパッチクランプ法 / 脊髄後角 / 興奮性シナプス伝達 / 痛み

Outline of Final Research Achievements

Intravenous administration of lidocaine (IVL) is used for the management of postoperative and neuropathic pain. However, the analgesic mechanisms of IVL are yet to be elucidated. We hypothesized that IVL may affect excitatory synaptic transmission in spinal dorsal horn neurons. Herein, we used in vivo patch-clamp recording to examine the effects of IVL on synaptic transmission in the dorsal horn neurons of adult male Wistar rats. The experiments were performed in the voltage-clamp mode at a holding potential of -70 mV. IVL (3 and 10 mg/kg) decreased sEPSC frequencies, but did not affect the amplitudes. IVL (10 mg/kg) also decreased the area under the curve of EPSCs evoked by peripheral pinch stimuli to the receptive field. However IVL, superfusion of lidocaine (100 μM) on the　spinal surface did not affect sEPSC frequencies or amplitudes. Our results suggest that IVL inhibits excitatory synaptic transmission in spinal dorsal horn neurons, which may be one of the analgesic mechanisms.

Free Research Field

麻酔科学