Serotonin-induced paw edema in the rat: pharmacological profile.
1. Serotonin (5-HT) induced a linear increase in paw weight in rats within 1 hr of an intraplantar injection (50 microliters vol) over a concentration range of 0.005-0.2 mg/ml. At the 0.2 mg/ml concentration, a 16-fold increase in paw weight was observed as compared to saline-injected controls. 2. Serotonin antagonists, such as LY53857, were the most effective antagonists of 5-HT induced paw swelling, producing near complete antagonism and an approximate ED50 of 0.1 mg/kg. A mixed 5-HT/histamine antagonist, cyproheptadine, also produced a nearly complete inhibition of the 5-HT response with an approximate ED50 of 1.3 mg/kg. 3. Dopamine agonists (pergolide, quinpirole), yohimbine, dexamethasone and nifedipine also produced a significant degree of antagonism of the 5-HT response. 4. Clonidine, prazocin, chlorpheniramine, cimetidine, various dopamine antagonists, imipramine, cyclosporine A, piroxicam and superoxide dismutase were all ineffective at altering the paw swelling response to 5-HT.
Cole
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Lilly Research Laboratories, Lilly Corporate Center, Eli Lilly and Co., Indianapolis, IN 46285, USA.
Brown
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Magee
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Magee
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Roudebush
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Bryant
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D000322:Adrenergic Agonists / Q000494:pharmacology; D018674:Adrenergic Antagonists / Q000494:pharmacology; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D002121:Calcium Channel Blockers / Q000494:pharmacology; D018491:Dopamine Agonists / Q000494:pharmacology; D018492:Dopamine Antagonists / Q000494:pharmacology; D004487:Edema / Q000139:chemically induced* / Q000188:drug therapy*; D006614:Hindlimb; D006633:Histamine Antagonists / Q000494:pharmacology; D007166:Immunosuppressive Agents / Q000494:pharmacology; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012701:Serotonin / Q000633:toxicity*; D012702:Serotonin Antagonists / Q000494:pharmacology
D000322:Adrenergic Agonists; D018674:Adrenergic Antagonists; D000894:Anti-Inflammatory Agents, Non-Steroidal; D002121:Calcium Channel Blockers; D018491:Dopamine Agonists; D018492:Dopamine Antagonists; D006633:Histamine Antagonists; D007166:Immunosuppressive Agents; D012702:Serotonin Antagonists; D012701:Serotonin