Cardiac damage in acute organophosphate poisoning in rats: Effects of atropine and pralidoxime☆

Abstract

Anticholinesterase poisoning is an important health problem in our country, and a complete understanding of its underlying mechanisms is essential for the emergency physician. Thus, we aimed to investigate the cardiac biochemical parameters and mortality in dichlorvos-induced poisoning in rats. Rats were randomly divided into 5 groups as control (corn oil), dichlorvos, atropine, pralidoxime, and atropine+pralidoxime groups. Immunohistochemical analyses of apoptosis and inducible nitric oxide synthase showed no change in cardiac tissue for all of the groups. Serum cholinesterase levels were suppressed with dichlorvos, and these reductions were inhibited with atropine and/or pralidoxime pretreatment. Serum levels of creatine kinase, creatine kinase-MB, cardiac troponin I, myoglobin, and N-terminal probrain natriuretic peptide were not affected with poisoning. Malondialdehyde and glutathione levels were not statistically significant between the groups. Although serum nitric oxide levels in the dichlorvos group were lower than those in the control group, cardiac nitric oxide levels in the atropine+pralidoxime group were markedly higher than those in the dichlorvos group. Atropine, pralidoxime, and atropine+pralidoxime pretreatments markedly reduced the mortality. In conclusion, our results implied that measured cardiac markers especially N-terminal probrain natriuretic peptide may not contribute to the early (first 6 hours) diagnosis of cardiotoxicity in dichlorvos-induced poisoning in rats. These results also showed that acute dichlorvos administration did not cause significant cardiac damage, and oxidative stress does not play a marked role in dichlorvos-induced poisoning. Besides, cardiac nitric oxide may produce protective effect on myocardium with atropine+pralidoxime therapy in rats.