Pharmacokinetics of intra-articular morphine in horses with lipopolysaccharide-induced synovitis

Analgesic efficacy of intra-articular morphine in experimentally induced radiocarpal synovitis in horses

“…1992), and strongly indicative of a peripherally mediated effect. A peripherally mediated effect also is indicated by high synovial concentrations of morphine in combination with very low serum concentration of morphine and the active metabolite morphine‐6‐glucuronide, detected in the present experiments (Lindegaard et al. 2010b).…”

“…Synovial fluid (approximately 3 mL at each sampling) was collected by repeated arthrocentesis using standard aseptic techniques with a 21‐gauge 40 mm needle, and immediately transferred into EDTA‐stabilized tubes. Blood and SF were sampled to study the inflammatory reaction and pharmacokinetics of IA morphine [reported elsewhere Lindegaard et al. (2010a, b)].…”

Modulation of Peripheral Sensory Neurons by the Immune System: Implications for Pain Therapy

“…Further studies have demonstrated anti-inflammatory effects Lindegaard et al, 2010b) and a lack of local tissue toxicity (Todhunter et al, 1996;Tulamo et al, 1996;Jaureguito et al, 2002). After intra-articular injec-PERIPHERAL PAIN INHIBITION tion, morphine was detectable in synovial fluid for up to 24 h but did not reach clinically significant concentrations in the systemic circulation (Lawrence et al, 1992;Tulamo et al, 1996;Richardson et al, 1997;Brandsson et al, 2000;Lindegaard et al, 2010a).…”

“…In human tissue sample, opioids have been shown to reduce proinflammatory cytokines, matrix metalloproteinase, and synovial leukocyte counts (Raap et al, 2000;Takeba et al, 2001;Straub et al, 2008). Intra-articular morphine injection decreased the number of inflammatory cells in synovial fluid of human patients with chronic arthritis and diminished joint swelling, synovial fluid protein content, and serum inflammatory parameters in horses with experimental synovitis in vivo (Lindegaard et al, 2010a). On the other hand, some studies found nonopioid proinflammatory effects of asimadoline (Machelska et al, 1999) and morphine (Perrot et al, 1999).…”

Managing orthopaedic pain in horses

“…Intrasynovial administration of 0.05 mg/kg morphine has also been demonstrated to provide analgesia for potentially 24 hours in experimentally induced radiocarpal joint synovitis (Lindegaard and others 2010a, b). …”