Soltaninejad_2007_Hum.Exp.Toxicol_26_963

Organophosphorus compounds are known to cause the selective release of liver microsomal beta-glucuronidase into plasma. Organophophoruses may induce nitrosative stress leading to the generation of nitrogen free radicals and alterations in scavengers of free radicals in many biological systems. In this study, we investigate how acute human organophosphorus intoxication is associated with changes of blood nitric oxide, total thiol molecules, and activities of the acetylcholinesterase and beta-glucuronidase. A total of 21 acute organophosphorus-poisoned patients were recruited into study and were divided into two groups of mildly (13) and severely affected (9); 26 age-matched healthy volunteers were recruited as control group. Results indicated that both mildly and severely affected patients had lower acetylcholinesterase activities as compared to controls. The extent of acetylcholinesterase reduction in the severely affected patients was higher than that of mildly affected patients. A significant increase in serum beta-glucuronidase was observed only in severely affected patients as compared to controls. Both mildly and severely affected patients had lower plasma total thiol molecules as compared to controls. The extent of reduction of total thiol molecules in the severely affected patients was higher than that of mildly affected patients. No significant difference was observed in plasma total nitric oxide of controls and patients. It is concluded that nitrosative stress has a minor role in toxicity of organophosphorus, whereas blood beta-glucuronidase is very sensitive biomarker at high exposure of severe organophosphorus poisoning.