FTOX016 In vitro effects of organophosphorus pesticide malathion on the reactivity of rat aorta.

Resumo

The organophosphorus (OF) compounds are chemicals present in pesticides and are known as acetylcholinesterase (AchE) inhibitors. The main toxic action of organophosphates includes the inhibition of cholinesterase enzyme promoting muscarinic, nicotinic and central effects. In the cardiovascular system, nicotinic manifestations are tachycardia and hypertension, while the muscarinic are bradycardia and hypotension. In the respiratory system cholinesterase, inhibition is characterized by increased bronchial secretions, bronchospasm and occurrence of paralysis of respiratory muscles. Although the effects of the organophosphates are best known due to inhibition of cholinesterase, in vitro studies have demonstrated its vasodilator effect and constriction of the airways, suggesting that these compounds may have a peripheral action independent of its effect on the enzyme that degrades acetylcholine. A better understanding of the toxic effects of organophosphates on the vascular system and respiratory systems, independent of cholinesterase inhibition, could open new perspectives for a more effective treatment directed to the major causes of death (respiratory failure and impaired cardiovascular function) in victims of poisoning these compounds.