[The effect of organophosphates on heart ATPase in the rat]

The effect of organophosphate intoxication with diisopropylfluorophosphate (DFP), paraoxon and parathion on the activity of some ATPases of rat hearts was examined. Biochemical and histochemical methods were employed to determine the activities of the transport ATPase, of the myofibres and mitochondrial ATPases using different doses and antidote application. The organophosphates studied here had an inhibitory effect on the activities of enzymes. Biochemical measurements showed that the ATPase activities are dependent upon the duration of poisoning, the dose of poison and the applied organophosphates. DFP caused the highest restriction in activity of the examined ATPases. The Ca2+-stimulated ATPase was more sensitive than the Na+/K+-ATPase to the application of organophosphates. The antidote therapy determined the grade of influence on activity. Combined treatments of organophosphate poisoning with atropine and obidoxime chloride in the high doses of 7.5 mg/kg and 12.5 mg/kg body weight i.m. proved to be the most effective against the organophosphate intoxication. Antidote combination of small doses and also single application of atropine or obidoxime chloride might cause a stimulation of activity of the Na+/K+-ATPase and a significant decline of the Ca2+-ATPase.