[Inhibition and stimulation of ATPase activity and the nonenzymatic hydrolysis of ATP in electron histochemistry (author's transl)].

In rat liver, homogenized and fractionated, ATPase activity was studied both histochemically and biochemically in the presence of lead ions and with addition of cysteine, EDTA, 2,4-DNP, sodium cyanide, sodium fluoride and p-chloromercuribenzoate. None of the inhibitors concerned permitted to obtain a complete inhibition of ATP hydrolysis. A practically complete inhibition of ATPase was possible only through heat inactivation or after double prefixation with formaldehyde and ethanol. Nonenzymatic ATP hydrolysis plays a negligible role in ATPase histochemistry since phosphate yield taking place due to lead action is insignificant against enzymatic hydrolysis of ATP.