Immersion autometallographic demonstration of pathological zinc accumulation in human acute neural diseases.

Zinc is the second most prevalent trace element in the body and is present in particularly large concentrations in the mammalian brain. In animal experiments, several lines of studies show that zinc is involved in the pathological process of ischemia, epilepsy, and mechanical head trauma. However, little is known about the change of zinc in the human neural diseases. In the present study, using immersion autometallography, we found that pathological zinc accumulation was extensively present in the human neurons following ischemia, epilepsy, and mechanical head trauma. Under H&E, apparently damaged neurons were observed in all of the brain regions that showed zinc ions labeled neuronal somata. In conclusion, the data provide the evidence of an active involvement of zinc in neuronal damage.