|
KMID : 0811720080120050237
|
|
Korean Journal of Physiology & Pharmacology
2008 Volume.12 No. 5 p.237 ~ p.244
|
|
|
Spinal Metabotropic Glutamate Receptors (mGluRs) are Involved in the Melittin-induced Nociception in Rats
|
|
Cho Chul-Hyun
Shin Hong-Kee
|
|
|
Abstract
|
|
|
|
Intraplantar injection of melittin has been known to induce sustained decrease of mechanical threshold and increase of spontaneous flinchings. The present study was undertaken to investigate how the melittin-induced nociceptive responses were modulated by changes of metabotropic glutamate receptor (mGluR) activity. Changes in paw withdrawal threshold (PWT), number of flinchings and paw thickness were measured at a given time point after injection of melittin (10?g/paw) into the mid-plantar area of rat hindpaw. To observe the effects of mGluRs on the melittin-induced nociceptions, group I mGluR (AIDA, 100?g and 200?g), mGluR1 (LY367385, 50?g and 100?g) and mGluR5 (MPEP, 200?g and 300?g) antagonists, group II (APDC, 100?g and 200?g) and III (L-SOP, 100?g and 200?g) agonists were intrathecally administered 20 min before melittin injection. Intraplantar injection of melittin induced a sustained decrease of mechanical threshold, spontaneous flinchings and edema. The effects of melittin to reduce mechanical threshold and to induce spontaneous flinchings were significantly suppressed following intrathecal pre-administration of group I mGluR, mGluR1 and mGluR5 antagonists, group II and III mGluR agonists. Group I mGluR antagonists and group II and III mGluR agonists had no significant effect on melittin-induced edema. These experimental findings indicate that multiple spinal mGluRs are involved in the modulation of melittin-induced nociceptive responses.
|
|
|
KEYWORD
|
|
|
Spinal metabotropic glutamate receptors, Melittin, Nociceptive responses
|
|
|
FullTexts / Linksout information
|
|
 
|
|
|
Listed journal information
|
|
  
|
|