The role of 5-HT1A and 5-HT1B receptors in spinal nociceptive transmission and in the modulation of NMDA induced behaviour.
The effects on nociception of intrathecal (i.th.) administration of selective 5-HT1A and 5-HT1B agonists were studied in rats. Nociception was evaluated using the tail-flick test with adjustments for tail-skin temperature, the increasing temperature hot-plate test and the scoring of biting and scratching behaviour after i.th. N-methyl-D-aspartate (NMDA). Activation of the spinal 5-HT1A receptor induced an antinociceptive effect in the increasing temperature hot-plate test and produced a dose dependent decrease in NMDA-receptor mediated behaviour. No significant change in nociception measured by either of the nociceptive tests was found after administration of the 5-HT1B agonist. These results support the hypothesis that spinal 5-HT1A receptor activation has an antinociceptive effect, and indicate a possible interaction between the serotonergic and glutaminergic transmitter systems.
Mjellem
N
N
Department of Physiology, University of Bergen, Norway.
Lund
A
A
Eide
P K
PK
Størkson
R
R
Tjølsen
A
A
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D006358:Hot Temperature; D007211:Indoles / Q000494:pharmacology; D007278:Injections, Spinal; D008297:Male; D016202:N-Methylaspartate / Q000494:pharmacology*; D010146:Pain / Q000503:physiopathology*; D010147:Pain Measurement / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D011930:Reaction Time / Q000187:drug effects; D011985:Receptors, Serotonin / Q000502:physiology*; D012701:Serotonin / Q000502:physiology*; D017366:Serotonin Receptor Agonists / Q000494:pharmacology; D012881:Skin Temperature / Q000187:drug effects; D013116:Spinal Cord / Q000502:physiology* / Q000503:physiopathology; D009435:Synaptic Transmission / Q000502:physiology*
D007211:Indoles; D011985:Receptors, Serotonin; D017366:Serotonin Receptor Agonists; C025145:5-methoxy 3-(1,2,3,6-tetrahydro-4-pyridinyl)1H indole; D012701:Serotonin; D016202:N-Methylaspartate; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin