Subcellular changes of essential metal shown by in-air micro-PIXE in oral cadmium-exposed mice

Nakazato, Kyomi*; Nagamine, Takeaki*; Suzuki, Keiji*; Kusakabe, Takahiko*; Moon, H. D.*; Oikawa, Masakazu*; Sakai, Takuro; Arakawa, Kazuo

To clarify the relation of essential metals to cadmium (Cd) toxicity, we evaluated metallothionein expression and analyzed the subcellular distribution of essential metals using in-air micro-PIXE. Four mice were dosed orally with 100 mg/L of Cd in drinking water for 1.5 or 2 years. Compared to the control, the Cd-exposed mice markedly accumulated zinc in the liver and renal cortex. Elemental maps showed that a large amount of Cd was spatially combined with zinc in the 1.5y-Cd mouse. The data suggest that zinc may contribute to protect against oral-administrated Cd toxicity.