MAPPING OF CALCIUM AND SODIUM IN HUMAN AMNION TISSUE-SECTIONS USING THE NUCLEAR MICROPROBE

The epithelial cell layer of the human amniotic membrane is an importa nt ionic exchanger zone. Na+ ions cross through cellular and paracellu lar pathways and Ca2+ ions interfere with these pathways. The ionic lo calization is underlying to understand the exchange mechanisms. The nu clear microanalysis is applied and quantitative mapping is carried out . The distribution of Na+ and Ca2+ is determined. In unwashed referenc e and in incubated amniotic specimens, Na+ and Ca2+ are located in epi thelial and compact layers. The Na+ concentration is identical in the two layers while the Ca2+ concentration increases in compact layer aft er incubation. These results suggest the importance of the compact lay er and explanations on ionic exchanges.