Nociceptive effects of intrathecal administration of sulphur-containing amino acids.
This study examined the nociceptive effects of the intrathecal administration of various doses of the following endogenous excitatory sulphur-containing amino acids (SAAs): L-cysteic acid (L-CA), L-cysteine sulfinic acid (L-CSA), L-homocysteic acid (L-HCA) and L-homocysteic sulfinic acid (L-HCSA). For a period of 10min, rats were observed for spontaneous nociceptive behaviours (SNBs), including: tail elevation, twitching or licking; hindpaw elevation, licking or shaking; and caudally directed biting or scratching. The amount of time each rat spent eliciting these individual behaviours was recorded and a total time (in seconds) spent exhibiting SNBs was then calculated. To determine which glutamate receptors are primarily responsible for these nociceptive behaviours, we pretreated additional groups of rats with selective antagonists for N-methyl-D-aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxazole proprionic acid/kainate (AMPA/KA) and group I metabotropic glutamate receptors (mGluR1 and 5). Results indicate that SAAs dose-dependently produce SNBs that are attenuated by NMDA receptor and group I mGluR antagonists.
Osborne
Michael G
MG
Anesthesia Research Unit, Department of Anesthesia, McGill University, 3655 Drummond Street, Montreal, Quebec, Canada H3G 1A4.
Coderre
Terence J
TJ
D000603:Amino Acids, Sulfur / Q000009:adverse effects*; D000818:Animals; D001522:Behavior, Animal; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D018846:Excitatory Amino Acids / Q000009:adverse effects; D007278:Injections, Spinal / Q000379:methods*; D008297:Male; D010146:Pain / Q000139:chemically induced* / Q000503:physiopathology; D010147:Pain Measurement / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
D000603:Amino Acids, Sulfur; D018846:Excitatory Amino Acids