Data/hora: 02/06/2024 09:27:05

Provedor de dados: | 56
País: | Brazil
Título: | Antipyretic and antioxidant activities of 5-trifluoromethyl-4,5-dihydro-1H-pyrazoles in rats
Autores: | Pasin,J.S.M.; Ferreira,A.P.O.; Saraiva,A.L.L.; Ratzlaff,V.; Andrighetto,R.; Machado,P.; Marchesan,S.; Zanette,R.A.; Bonacorso,H.G.; Zanatta,N.; Martins,M.A.P.; Ferreira,J.; Mello,C.F.
Data: | 2010-12-01
Ano: | 2010
Palavras-chave: | Pyrazole derivatives; Fever; Cytokine levels; Cyclooxygenase.
Resumo: | The objective of this study was to determine the effect of eight 5-hydroxy-5-trifluoromethyl-4,5-dihydro-1H-1-carboxyamidepyrazoles (TFDPs) on rat body temperature and baker’s yeast-induced fever. TFDPs or vehicle (5% Tween 80 in 0.9% NaCl, 5 mL/kg) were injected subcutaneously and rectal temperature was measured as a function of time in 28-day-old male Wistar rats (N = 5-12 per group). Antipyretic activity was determined in feverish animals injected with baker’s yeast (Saccharomyces cerevisiae suspension, 0.135 mg/kg, 10 mL/kg, ip). 3-Ethyl- and 3-propyl-TFDP (140 and 200 μmol/kg, respectively, 4 h after yeast injection) attenuated baker’s yeast-induced fever by 61 and 82%, respectively. These two effective antipyretics were selected for subsequent analysis of putative mechanisms of action. We then determined the effects on cyclooxygenase-1 and -2 (COX-1 and COX-2) activities on 1,1-diphenyl-2-picrylhydrazyl (DPPH) oxidation in vitro, on tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) levels and on leukocyte counts in the washes of peritoneal cavities of rats injected with baker’s yeast. While 3-ethyl- and 3-propyl-TFDP did not reduce baker’s yeast-induced increases of IL-1β or TNF-α levels, 3-ethyl-TFDP caused a 42% reduction in peritoneal leukocyte count. 3-Ethyl- and 3-propyl-TFDP did not alter COX-1 or COX-2 activities in vitro, but presented antioxidant activity in the DPPH assay with an IC50 of 39 mM (25-62) and 163 mM (136-196), respectively. The data indicate that mechanisms of action of these two novel antipyretic pyrazole derivatives do not involve the classic inhibition of the COX pathway or pyrogenic cytokine release.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2010001200009
Editor: | Associação Brasileira de Divulgação Científica
Relação: | 10.1590/S0100-879X2010007500139
Formato: | text/html
Fonte: | Brazilian Journal of Medical and Biological Research  v.43 n.12 2010
Fonte: | info:eu-repo/semantics/openAccess