BACKGROUND: Nitrergic and prostanoid pathways have both been implicated in inflammatory processes. OBJECTIVE: To investigate their respective contributions in a rat model of chronic arthritis. METHODS: Male Wistar rats (n = 4-6/group) received either an intra-articular injection of 2% carrageenan/4% kaolin (C/K) or intra- and periarticular injections of Freund's complete adjuvant (FCA; 10 mg/ml M tuberculosis). Joint diameter, urinary nitric oxide metabolites (NO(x)), and prostaglandin E(2) (PGE(2)) levels were measured as indices of the inflammatory process. A prophylactic and therapeutic (day 5) dose ranging study of an inducible nitric oxide synthase inhibitor, L-N-(1-iminoethyl)-lysine (L-NIL), and a cyclo-oxygenase-2 (COX-2) inhibitor, SC-236, was performed with the drugs given subcutaneously. Submaximal doses were identified and used for combination studies. Appropriate vehicle controls were included. RESULTS: L-NIL and SC-236 dose dependently inhibited C/K induced acute joint swelling, the magnitude being greatest when they were given in combination. Both prophylactic and therapeutic administration of SC-236 in the FCA induced model of chronic arthritis produced a dose dependent reduction in all the measures assessed. However, although L-NIL demonstrated similar dose dependent inhibition of urinary NO(x) and PGE(2) levels, joint swelling was significantly exacerbated in this model. Co-administration of the inhibitors nullified the benefits of SC-236. CONCLUSION: Whereas COX-2 derived prostaglandins are proinflammatory in both acute and chronic joint inflammation, NO seems to have divergent roles, being anti-inflammatory in chronic and proinflammatory in acute joint inflammation.
BACKGROUND: Nitrergic and prostanoid pathways have both been implicated in inflammatory processes. OBJECTIVE: To investigate their respective contributions in a rat model of chronic arthritis. METHODS: Male Wistar rats (n = 4-6/group) received either an intra-articular injection of 2% carrageenan/4% kaolin (C/K) or intra- and periarticular injections of Freund's complete adjuvant (FCA; 10 mg/ml M tuberculosis). Joint diameter, urinary nitric oxide metabolites (NO(x)), and prostaglandin E(2) (PGE(2)) levels were measured as indices of the inflammatory process. A prophylactic and therapeutic (day 5) dose ranging study of an inducible nitric oxide synthase inhibitor, L-N-(1-iminoethyl)-lysine (L-NIL), and a cyclo-oxygenase-2 (COX-2) inhibitor, SC-236, was performed with the drugs given subcutaneously. Submaximal doses were identified and used for combination studies. Appropriate vehicle controls were included. RESULTS:L-NIL and SC-236 dose dependently inhibited C/K induced acute joint swelling, the magnitude being greatest when they were given in combination. Both prophylactic and therapeutic administration of SC-236 in the FCA induced model of chronic arthritis produced a dose dependent reduction in all the measures assessed. However, although L-NIL demonstrated similar dose dependent inhibition of urinary NO(x) and PGE(2) levels, joint swelling was significantly exacerbated in this model. Co-administration of the inhibitors nullified the benefits of SC-236. CONCLUSION: Whereas COX-2 derived prostaglandins are proinflammatory in both acute and chronic joint inflammation, NO seems to have divergent roles, being anti-inflammatory in chronic and proinflammatory in acute joint inflammation.
Authors: C Cicala; A Ianaro; S Fiorucci; A Calignano; M Bucci; R Gerli; L Santucci; J L Wallace; G Cirino Journal: Br J Pharmacol Date: 2000-07 Impact factor: 8.739
Authors: I B McInnes; B P Leung; M Field; X Q Wei; F P Huang; R D Sturrock; A Kinninmonth; J Weidner; R Mumford; F Y Liew Journal: J Exp Med Date: 1996-10-01 Impact factor: 14.307
Authors: Leila M Sevigny; Ping Zhang; Andrew Bohm; Katherine Lazarides; George Perides; Lidija Covic; Athan Kuliopulos Journal: Proc Natl Acad Sci U S A Date: 2011-05-02 Impact factor: 11.205
Authors: Petra Hartmann; Edina Butt; Ágnes Fehér; Ágnes Lilla Szilágyi; Kurszán Dávid Jász; Boglárka Balázs; Mónika Bakonyi; Szilvia Berkó; Gábor Erős; Mihály Boros; Gyöngyi Horváth; Endre Varga; Erzsébet Csányi Journal: Drug Des Devel Ther Date: 2018-06-27 Impact factor: 4.162