title: New index of pain triggered by spinal activation of voltage-dependent sodium channels.
abstract: Voltage-dependent sodium channels (VDSCs) are crucial for pain generation. Here, to develop a new behavioral index of pain induced by spinal VDSC activation, we examined whether intrathecal veratridine injection produced nociceptive behavior. Intrathecal injection of the VDSC opener veratridine in mice dose-dependently induced nociceptive responses, with response times subsequently reduced by administration of morphine or pregabalin. Systemic administration of lidocaine and mexiletine, but not amitriptyline, also decreased this response time. Taken together, these results demonstrated that response time of nociceptive behavior induced by intrathecal veratridine injection is a quantitative index of pain triggered by spinal VDSC activation.
authors.affiliation: Pharmacology Research Laboratories, Astellas Pharma Inc., Miyukigaoka 21, Tsukuba, Ibaraki, 305-8585, Japan, ryuugo.enomoto@astellas.com.
authors.forename: Ryugo
authors.initials: R
authors.lastname: Enomoto
authors.forename: Mina
authors.initials: M
authors.lastname: Tsukamoto
authors.forename: Yukinori
authors.initials: Y
authors.lastname: Shimoshige
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Aoki
authors.forename: Nobuya
authors.initials: N
authors.lastname: Matsuoka
mesh_terms: D000639:Amitriptyline / Q000494:pharmacology; D000818:Animals; D007278:Injections, Spinal; D008012:Lidocaine / Q000494:pharmacology; D008297:Male; D008801:Mexiletine / Q000494:pharmacology; D051379:Mice; D008813:Mice, Inbred ICR; D009020:Morphine / Q000494:pharmacology; D059226:Nociceptive Pain / Q000139:chemically induced* / Q000188:drug therapy; D059408:Pain Management / Q000379:methods*; D010147:Pain Measurement / Q000379:methods*; D000069583:Pregabalin; D013131:Spine / Q000187:drug effects* / Q000378:metabolism; D061585:Voltage-Gated Sodium Channel Agonists / Q000494:pharmacology*; D061566:Voltage-Gated Sodium Channels / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000031:analogs & derivatives / Q000494:pharmacology
chemical_list: D061585:Voltage-Gated Sodium Channel Agonists; D061566:Voltage-Gated Sodium Channels; D000639:Amitriptyline; D008801:Mexiletine; D000069583:Pregabalin; D005680:gamma-Aminobutyric Acid; D009020:Morphine; D008012:Lidocaine