Comparison of the accumulation of 125I and 144Ce in the growing oocytes of the Japanese quail.

Japanese quail were doubly-labeled with 125I (carrier free, as sodium iodide) and 144Ce (.015 micromol/100 g, as trichloride). by 1 hr after administration, the growing oocytes and the ova had accumulated 29% of the 125I and 21% of the 144Ce. By 18 hr, the accumulations were 30% of the 125I and 79% of the 144Ce. Lanthanum (15 micromol/100 g, as trichloride), given iv 5 min before the radionuclides, resulted in 1-hr accumulations of 4% for 125I and 23% for 144Ce. On fractionation of the oocyte yolk, 86% of the 125I present in the yolk was found in the low density fraction and 69% of the 144Ce remained with the phosvitin fraction. These results were consistent with the suggestion of Schjeide and Prahlad (1977) that, in plasma, iodide becomes associated with the calcium-containing vitellogenin complex.