title: In vivo effects of carprofen, deracoxib, and etodolac on prostanoid production in blood, gastric mucosa, and synovial fluid in dogs with chronic osteoarthritis.
abstract: OBJECTIVE
  To evaluate in vivo activity of carprofen, deracoxib, and etodolac on prostanoid production in several target tissues in dogs with chronic osteoarthritis.
  
  
  METHODS
  8 dogs with chronic unilateral osteoarthritis of the stifle joint.
  
  
  METHODS
  Each dog received carprofen, deracoxib, or etodolac for 10 days with a 30- to 60-day washout period between treatments. On days 0, 3, and 10, prostaglandin (PG) E2 concentrations were measured in lipopolysaccharide-stimulated blood, synovial fluid, and gastric mucosal biopsy specimens; PGE1 concentrations were measured in gastric mucosal biopsy specimens; and thromboxane B2 (TXB2) was evaluated in blood.
  
  
  RESULTS
  Carprofen and deracoxib significantly suppressed PGE2 concentrations in blood at days 3 and 10, compared with baseline, whereas etodolac did not. None of the drugs significantly suppressed TXB2 concentrations in blood or gastric PGE1 synthesis at any time point. All 3 drugs significantly decreased gastric synthesis of PGE2 at day 3 but not day 10 of each treatment period. All 3 drugs decreased synovial fluid PGE2 concentrations in the affected and unaffected stifle joints at days 3 and 10.
  
  
  CONCLUSIONS
  Results indicate that carprofen and deracoxib act in vivo on target tissues as COX-1-sparing drugs by sparing gastric PGE1 and PGE2 synthesis and production of TXB2 by platelets. Etodolac also appears to be COX-1 sparing but may have variable effects on COX-2 depending on the tissue. In gastric mucosa and synovial fluid, there were no significant differences in PG production between compounds at recommended concentrations.
authors.affiliation: Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA.
authors.forename: John K
authors.initials: JK
authors.lastname: Sessions
authors.forename: Lisa R
authors.initials: LR
authors.lastname: Reynolds
authors.forename: Steven C
authors.initials: SC
authors.lastname: Budsberg
mesh_terms: D000818:Animals; D002227:Carbazoles / Q000494:pharmacology; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D015232:Dinoprostone / Q000096:biosynthesis* / Q000097:blood; D004283:Dog Diseases / Q000188:drug therapy* / Q000378:metabolism; D004285:Dogs; D004334:Drug Administration Schedule; D017308:Etodolac / Q000494:pharmacology; D005753:Gastric Mucosa / Q000378:metabolism*; D010003:Osteoarthritis / Q000188:drug therapy / Q000662:veterinary*; D013449:Sulfonamides / Q000494:pharmacology; D013582:Synovial Fluid / Q000378:metabolism*; D000096926:Benzenesulfonamides
chemical_list: D002227:Carbazoles; D016861:Cyclooxygenase Inhibitors; D015232:Dinoprostone; D017308:Etodolac; D013449:Sulfonamides; C007005:carprofen; C471996:deracoxib; D000096926:Benzenesulfonamides