Uptake and distribution of Cd in the ovaries, adrenals, and pituitary in pseudopregnant rats: effect of Cd on progesterone serum levels.

Pseudopregnant (PSP) rats were treated with 3.5 or 7.0 mg/kg body wt of CdCl2 on Day 1 of PSP sc. In the lower dose Cd content of the ovaries (luteal and nonluteal tissues), adrenals, pituitary, and blood on Days 1, 2, 5, 8, 10, and 12, and in the higher dose that of luteal and nonluteal tissue on Days 2 and 5 of PSP were determined with atomic absorption spectrophotometry. A rapid incorporation into the corpora lutea was measured on Day 1 and Day 2 of PSP followed by a decrease of Cd content toward the end of PSP whereas the nonluteal tissue, adrenals, and pituitary accumulated Cd gradually until the fifth to 10th day, respectively. Progesterone (P) serum levels were measured with RIA in the blood collected daily from the jugular vein following administration of 3.5 to 7.0 mg/kg body wt of CdCl2 sc on Day 1 or Day 8 of PSP. The serum levels of P remained unchanged when CdCl2 was administered on Day 1 of PSP; however, 7.0 mg/kg body wt CdCl2 given on Day 8 of PSP induced a significant decrease in serum levels of P. It is supposed that the regressing luteal tissue is more sensitive to the toxic effects of Cd than the developing one.