Detoxication of poisoning by 11 metals by quinamic acid

Quinamic acid, bis-(3-carboxy-5-N-dicarboxymethyl-aminomethyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinolinyl-8)-5,8-dimethyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid is a new chelating agent first synthesized in this Institute. Quinamic acid iv 500 mg/kg markedly reduced the mortality of acute ip poisoning of ZnSO4,NiCl2,CdCl2, and UO2(N03)2 in mice(P<0.01). After ip uranyl nitrate (400 microg U/rat) following im quinamic acid 100 mg/rat, there was also an enhanced excretion of uranium in urine. The urinary U amounted to 49%±16% of the administered dose, whereas only 26%±8% in the control in 48 h. Within 2 weeks, treated rats showed less toxic reactions and renal damages than the control rats.The activity of urinary catalase in treated rats was significantly lower than that in controls.