Inflammatory animal models

Dynorphin may also influence nociception at the spinal level. The levels of prodynorphin mRNA and immunoreactive dynorphin increase in the chronic inflammatory arthritic model (158). Dynorphin also inhibits morphine or P-endorphin-induced analgesia in naive animals and enhances analgesia in tolerant animals, indicating that this peptide may have a regulatory role in opioid analgesia (159). This effect does not appear to be mediated by a classical opioid receptor, since des-tyrosine dynorphin, which does not bind to opioid receptors, also antagonizes morphine analgesia (160). 

While the obvious value of in vivo animal models is clear, there also are instances—especially in cases of inflammatory arthritis, behavior, and tumor growth—where they have failed to be predictive of useful clinical activity in humans [51], For example, leukotriene (LTB4) antagonists showed activity in animal models of inflammatory arthritis yet failed to be useful in rheumatoid arthritis [52]. Similarly, dopamine D4 antagonists showed activity in animal behavior models previously predictive of dopamine D2 antagonists in schizophrenia. However, testing of dopamine D4 antagonists showed no efficacy in humans [53]. 

Colon inflammation 1. AEA levels are elevated in the colon of DNBS-treated mice and in the colon submucosa of TNBS-treated rats, two animal models of inflammatory bowel diseases, and in the biopsies of patients with ulcerative colitis, to control inflammation 1. Inhibitors of degradation (both FAAH and cellular re-uptake)... 

Index for anti-inflammatory activity. Model acute inflammation, method Carragennan induced edema, test animal albino rats, number of animals per group 6, route of administration oral, standard phenylbutazone (100 mgkg ), test compounds lOOmgkg ... 

A number of diflFerent animal models of uveitis have been developed) including that induced by organ-specific ocular antigens such as retinal S-antigen, rhodopsin and lens protein (Wacker et al., 1977 Rao et al., 1979). Other models are based on the injection of proteins foreign to the host, such as intravitreal injections of albumin or 7-globulin (Zimmerman and Silverstein, 1959 Kaplan etal., 1979). More recently, a third group of models has been developed based on the injection of inflammatory mediators such as interleukins-1 and 2, and tumour necrosis factor (Bhattacherjee and Henderson, 1987 ... 

Polansky, J. and Weinreb, B. (1984). Anti-inflammatory agents steroids as anti-inflammatory agpnts. In Pharmacology of the Eye (ed. M.L. Sears) pp. 459-538. Springer Verl, Berlin. Rao, N., Romero, J., Fernandez, M. and Marak, G.E. (1986). Effect of iron chelation on severity of occular inflammation in an animal model. Arch. Ophthalmol. 104, 1369-1371. 

There is now little doubt that ROMs are produced in excess in patients with aaive IBD. That, at least in experimental colitis, they are rather more than irrelevant epiphenomena is indicated by the anti-inflammatory effect of specific antioxidants. Proof that this is also the case in human disease awaits the outcome of further controlled trials of specific agents interfering with ROM production. Whilst induction of NO production has been shown to occur in association with inflammation and tissue damage in both humans and in animal models, the significance of this is as yet unclear. 

Compound (20) eventually emerged as an optimized lead (EC50 = 4nM) with satisfactory pharmacokinetic and solubility properties as well as potent activity in animal models of visceral and chronic inflammatory pain [85]. 

There is concern regarding administration of dexamethasone to patients with pneumococcal meningitis caused by penicillin- or cephalosporin-resistant strains, for which vancomycin would be required. Animal models indicate that concurrent steroid use reduces vancomycin penetration into the CSF by 42% to 77% and delays CSF sterilization due to reduction in the inflammatory response.23 Treatment failures have been reported in adults with resistant pneumococcal meningitis who were treated with dexamethasone, but the risk-benefit of using dexamethasone in these patients cannot be defined at this time. Animal models indicate a benefit of adding rifampin in patients with resistant pneumococcal meningitis whenever dexamethasone is used.21,23... 

Weekes J et al. Bovine dilated cardiomyopathy proteomic analysis of an animal model of human dilated cardiomyopathy Electrophoresis 1999 20 898-906. Doherty NS et al. Analysis of changes in acute phase plasma proteins in an acute inflammatory response and in rheumatoid arthritis using two-dimensional gel electrophoresis. Electrophoresis 1998 19 355-363. 

Although infection with C. parvum is considered predominantly secretory, histopathologic studies have revealed varying degrees of villous atrophy and infiltration of inflammatory cells beneath the epithelial mucosa [85, 86], Prostaglandins, which are known to induce cAMP-mediated apical chloride secretion and inhibit electroneutral sodium chloride and water absorption in enterocytes, have been demonstrated to be elevated in a porcine model of cryptosporidiosis [87], Inflammatory cytokines such as IL-1, IL-8 and TNF-a are induced in intestinal epithelial cell lines infected with Cryptosporidium and in animal models of cryptosporidiosis and have been postulated to play a role in pathogenesis [88, 89], Expression of TNF-a and IL-1 mRNA in the majority of jejunal biopsies of adult volunteers after experimental infection were also observed, although this did not correlate with the enteric symptoms [90]. 

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