Visual imaging of ion distribution in human epidermis

The distribution of calcium, magnesium, potassium, sodium, and hydrogen ion s in the human epidermis was visualized by blotting to gel containing chemi cal indicators and the effects of skin barrier disruption were examined. In normal skin, both calcium and magnesium were localized with high concentra tion in the upper epidermis. EDTA blocked these imaging. The hydrogen ion w as also high in the upper epidermis. Sodium did not show obvious gradation in the epidermis. The potassium concentration was the lowest in the upper e pidermis. After the barrier disruption, the gradients of calcium, magnesium , and potassium disappeared while the pH gradation was not altered. Observa tion at a high magnification revealed lower calcium and sodium concentratio ns in the nucleus. The concentration of magnesium was slightly higher in th e nucleus. The novel method of the present study could show the visual imag e of the ions in frozen tissue without further preparation, (C) 2000 Academ ic Press.