Pharmacological profile of rat pleurisy induced by Bothrops jararaca venom.
Bothrops jararaca venom (30 micrograms/site) triggered a marked inflammatory reaction in the pleural cavity that was long-lasting and reproducible. In the first 1 h after pleurisy induction, a significant decrease of total and differential cell count was observed in comparison with control values, despite the gradual enhancement of fluid leakage. A significant increase of cell migration was observed after 3 h of pleurisy induction, due to mononuclear and neutrophil cells that peaked 8 h later and this was followed by a gradual decrease, remaining elevated up to 24 h. In parallel with cell influx, a significant increase of fluid leakage that peaked between 1 and 8 h was observed, being completely abolished after 12 h following pleurisy induction. This inflammatory response was not associated in parallel with significant changes in circulating leucocyte cells and it was significantly inhibited by compound 48/80, cyproheptadine, pyrilamine, dexamethasone, indomethacin and phenidone. Preheating of the venom (100 degrees C) caused a significant decrease of both leakage of fluid and cell migration in the pleural cavity 8 h after pleurisy induction. Previous exposure to the venom (30 micrograms/site, 5 days before) produced a significant decrease of both cell migration and fluid leakage 4 h after triggering pleurisy with the same dose of the venom. Otherwise, prior daily treatment with the venom (10 micrograms/site, 4 days) resulted only in marked fluid leakage reduction 1 h after treating the animals with BJV (30 micrograms/site). These results show that the venom elicits pro-inflammatory effects in the rat pleural cavity which involve the participation of several mediators, including histamine, 5-hydroxytryptamine and products of arachidonic pathways.
Búrigo
A C
AC
Department of Pharmacology, CCB, UFSC, R. Ferreira Lima, SC, Brazil.
Calixto
J B
JB
Medeiros
Y S
YS
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D016718:Arachidonic Acid / Q000378:metabolism; D017837:Bothrops; D002452:Cell Count / Q000187:drug effects; D003435:Crotalid Venoms / Q000633:toxicity*; D003533:Cyproheptadine / Q000494:pharmacology; D003907:Dexamethasone / Q000494:pharmacology; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D006636:Histamine Release / Q000187:drug effects; D007213:Indomethacin / Q000494:pharmacology; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000187:drug effects; D016859:Lipoxygenase Inhibitors / Q000494:pharmacology; D008297:Male; D009504:Neutrophils / Q000166:cytology / Q000187:drug effects; D010998:Pleurisy / Q000139:chemically induced* / Q000473:pathology; D011720:Pyrazoles / Q000494:pharmacology; D011738:Pyrilamine / Q000494:pharmacology; D051381:Rats; D012701:Serotonin / Q000378:metabolism; D003189:p-Methoxy-N-methylphenethylamine / Q000494:pharmacology
D000894:Anti-Inflammatory Agents, Non-Steroidal; D003435:Crotalid Venoms; D006634:Histamine H1 Antagonists; D016859:Lipoxygenase Inhibitors; D011720:Pyrazoles; D016718:Arachidonic Acid; D003533:Cyproheptadine; D012701:Serotonin; D003189:p-Methoxy-N-methylphenethylamine; D003907:Dexamethasone; C015429:phenidone; D011738:Pyrilamine; D007213:Indomethacin