Relation between 67Ga uptake and iron metabolism in rat tissues.

The relationship between 67Ga uptake and iron metabolism was investigated in rat tissues. 67Ga and 59Fe(II) both accumulated in the mitochondrial-lysosomal fraction after being injected. Moreover, they both showed especially high affinity for heparan sulfate (HS) among various acid mucopolysaccharides (AMPS). When iron (ferrous citrate) was injected IV before, simultaneously with, and after 67Ga citrate IV injection, 67Ga uptake was significantly inhibited in normal rat liver in all cases. Elevated 67Ga uptake in the liver of CCl4-treated rats was also lowered to the control level by iron pretreatment. High zinc intake remarkably elevated the 67Ga uptake in rat liver. The contents of iron in the liver and liver AMPS of 0.75% zinc-fed rats were lowered in comparison with those in controls. Thus, the elevation of 67Ga uptake in the liver of zinc-fed rats might be due to the decrease of iron bound to HS.