Document Type : Research article
Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, P. O. Box: 1177, Urmia University, Urmia, Iran.
Department of Molecular Genetic, Faculty of Basic Sciences, Urmia University, Urmia, Iran.
Department of Histology and Embryology, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran.
Paraquat is a commonly used herbicide in many countries which can lead to systematic poisoning on exposure, In this study, paraquat (PQ)-induced changes in the expression of Cyclooxygenase-2 (COX-2) along with biochemical and histopathological changes in the lungs, liver and kidneys were studied. Twenty four male Wistar rats (180-200 g) were exposed either against saline as control group or various doses of PQ (3.5, 7 and 10 mg/kg, SC) as test groups for 7 consecutive days. The animals in test groups demonstrated a significant increase of malondialdehyde and NO contents, while a remarkable decrease of total thiol molecules was recorded. Histopathological studies revealed a severe alveolar edema and hemorrhages in the lungs, congestion and glycogen degeneration in the liver and multifocal interstitial nephritis along with proximal tubular degeneration in the kidneys. PQ up-regulated the COX-2 expression at mRNA level significantly in the examined organs. This data suggest that the PQ-induced oxidative disturbances and pathological damages can be attributed to the upregulation of COX-2 in examined organs.