INVESTIGATING RESPONSE OF SPLEEN AND ERYTHROCYTES ANTIOXIDANT DEFENSE SYSTEM ON THE EFFECTS OF NACETYL CYSTEINE AGAINST PARAOXON TOXICITY IN RAT

Paraoxon (POX) as an organophosphate pesticide is the active form of parathion
that is widely used in agriculture. Antioxidants can protect cells from oxidative stress. The aim of this
study was to investigate the effect of NAC as an antioxidant against POX- induced oxidative stress in
rat spleen and erythrocytes.
Material & Methods: In the present experimental study, male Wistar rats were randomly divided into
four groups including: control group (corn oil as POX solvent), POX group (0.7 mg/kg), NAC group
(160 mg/kg), and NAC+POX all of which were given intraperitoneally. Then, 24 hours after injection,
the animals were anesthetized, spleen tissues were quickly removed and blood was also collected by
cardiac puncture; and erythrocytes were obtained. Then, superoxide dismutase (SOD), catalase (CAT)
and glutathione S-transferase (GST) activities, as well as glutathione (GSH) and malondialdehyde
(MDA) levels were determined by biochemical methods.
Results: POX increased SOD and GST activities and decreased GSH content in rat spleen and
erythrocytes. Also, POX increased CAT activity and MDA level in erythrocytes and decreased CAT
activity in spleen. Administration of NAC inhibited the changes in these parameters.
Conclusion: POX with free radical production and depleted GSH content leads to oxidative stress
induction in spleen and erythrocytes. Administration of NAC as antioxidant decreases POX-induced
oxidative stress by scavenging free radicals and GSH synthesis, but it does not protect completely.