Physiological importance of the connective tissue in the human amnion. Role of magnesium

The elemental ionic distribution in the epithelial layer (EL) and in connective tissue (CT = compact layer + fibroblast layer) of the human amniotic membrane has been studied in reference samples, after conservation in a physiological fluid (Hanks' solution) and after addition of 2 mM MgCl2 in Hanks' solution. Particle induced X-ray emission and Rutherford backscattering spectrometry techniques were used to provide quantitative measurements. In physiological fluid, with regard to reference samples, the monovalent ions (Na+, K +, Cl-) concentrations were identical on both layers. This data indicates that the connective tissue, in particular the compact layer, acts as a buffer which fix minerals. Mg2+ and Ca2+ levels were higher in EL than in CT. The addition of MgCl2 in Hanks' solution induced a decrease of the monovalent ion concentrations in both layers except Na+ level in EL which remained constant, an increase of the Mg2+ level in both layers, while the Ca2+ remained constant. These data indicate the possible role of connective tissue in pregnancies complicated by poly or oligohydramnios.