RESUMO
Objectives: The effects of hydroalcoholic extract of Zataria multiflora (Z. multiflora) on memory changes, as well as lung injury due to inhaled paraqut (PQ) in rat, were examined.Method: Control group of rat with saline aerosol administration, PQ groups with PQ aerosol (27 and 54 mg/m3) administration, PQ groups treated with two doses of the extract (200 and 800 mg/kg/day) and dexamethasone (0.03 mg/kg/day) were studied. Shuttle box and Morris Water Maze (MWM) tests were carried out as well as oxidant, anti-oxidant markers, total and differential white blood cell (WBC) counts and cytokine levels in broncho-alveolar lavage (BALF).Results: Inhaled PQ significantly increased the escape latency and travelled distance in MWM test, but the time spent in the target quadrant on the probe day was significantly reduced (p < 0.05 to p < 0.001). The latency to enter the dark room at 3, 24, and 48 h after an electrical shock was reduced due to PQ (p < 0.05 to p < 0.001). Exposure to PQ significantly increased total WBC, neutrophil, eosinophil, lymphocyte, and monocyte counts, IL-10, interferon gama (INF-γ), nitrite (NO2), and malondialdehyde (MDA) levels, but catalase (CAT), superoxide dismutase (SOD), and thiol levels were decreased (p < 0.05 to p < 0.00). Z. multiflora and dexamethasone treatment significantly improved all behavioral as well as lung changes induced by inhaled PQ (p < 0.05 to p < 0.01).Conclusion: Z. multiflora treatment improved learning and memory impairment as well as lung inflammation and oxidative stress induced by inhaled PQ.