Tadalafil analgesia in experimental arthritis involves suppression of intra-articular TNF release.
Br J Pharmacol
; 164(2b): 828-35, 2011 Sep.
Article
em En
| MEDLINE
| ID: mdl-21557731
BACKGROUND AND PURPOSE: We investigated the effect of the phosphodiesterase-5 inhibitor, tadalafil, on the acute hypernociception in rat models of arthritis. EXPERIMENTAL APPROACH: Rats were treated with either an intra-articular injection of zymosan (1 mg) or surgical transection of the anterior cruciate ligament (as an osteoarthritis model). Controls received saline intra-articular or sham operation respectively. Joint pain was evaluated using the articular incapacitation test measured over 6 h following zymosan or between 4 and 7 days after anterior cruciate ligament transection. Cell counts, tumour necrosis factor-α (TNF-α), interleukin-1 (IL-1), and the chemokine, cytokine-induced neutrophil chemoattractant-1 (CINC-1) were measured in joint exudates 6 h after zymosan. Groups received tadalafil (0.02-0.5 mg·kg⻹ per os) or saline 2 h after intra-articular zymosan. Other groups received the µ-opioid receptor antagonist naloxone or the cGMP inhibitor 1H-[1,2,4] oxadiazolo [4,3-a] quinoxalin-1-one (ODQ) before tadalafil. KEY RESULTS: Tadalafil dose-dependently inhibited hypernociception in zymosan and osteoarthritis models. In zymosan-induced arthritis, tadalafil significantly decreased cell influx and TNF-α release but did not alter IL-1 or CINC-1 levels. Pretreatment with ODQ but not with naloxone prevented the anti-inflammatory effects of tadalafil. CONCLUSIONS AND IMPLICATIONS: Therapeutic oral administration of tadalafil provided analgesia mediated by guanylyl cyclase and was independent of the release of endogenous opioids. This effect of tadalafil was associated with a decrease in neutrophil influx and TNF-α release in inflamed joints.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Artrite Experimental
/
Carbolinas
/
Fator de Necrose Tumoral alfa
/
Nociceptividade
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Br J Pharmacol
Ano de publicação:
2011
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Reino Unido