Receptor mediation of 5-HT-induced inflammation and nociception in rats.
In light of evidence suggesting the proinflammatory and nociceptive action of peripheral serotonin (5-HT), the present study examined dose-dependent parameters of edema and algesia produced by intraplantar injections of 5-HT and the role of heterogeneous 5-HT receptors in these 5-HT-induced responses. Intraplantar 5-HT (0.05, 0.25, 0.5, or 1.0 mumols) produced paw edema at each 5-HT concentration and produced concentration-dependent increases in the nociceptive response as indexed by lifts of, and licks to the affected paw. Intraplantar pretreatment with the 5-HT1 receptor antagonist methysergide at concentrations greater than or equal to 3 nmol attenuated the 5-HT-induced (25 mumols) inflammatory and nociceptive responses. At concentrations greater than or equal to 300 nmol, both 5-HT2 receptor antagonist ketanserin and 5-HT3 receptor antagonist odansetron pretreatment blocked 5-HT-induced inflammatory and nociceptive responses. These results more completely define peripheral 5-HT-receptor-dependent systems of 5-HT-induced inflammation and nociception in rats.
Sufka
K J
KJ
Neuropharmacology Laboratory, College of Pharmacy and Health Sciences, Drake University, Des Moines, IA 50311-4505.
Schomburg
F M
FM
Giordano
J
J
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D007093:Imidazoles / Q000494:pharmacology; D007249:Inflammation / Q000139:chemically induced / Q000503:physiopathology*; D007650:Ketanserin / Q000494:pharmacology; D008297:Male; D008784:Methysergide / Q000494:pharmacology; D017294:Ondansetron; D010146:Pain / Q000139:chemically induced / Q000503:physiopathology*; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000187:drug effects / Q000502:physiology*; D012701:Serotonin / Q000494:pharmacology*; D012702:Serotonin Antagonists / Q000494:pharmacology
D007093:Imidazoles; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D012701:Serotonin; D017294:Ondansetron; D007650:Ketanserin; D008784:Methysergide