Calcium-cadmium competition in ovarian vitellogenic follicles of Galleria mellonella as revealed by X-ray microanalysis

Dissected ovarioles of Galleria mellonella were exposed for 60 min to cadmium, supplied to insect culture medium in amount equalling that of calcium therein. The sections of ovarioles treated with a fixative precipitating both elements and embedded in epon were examined using energy-dispersive X-ray microanalysis system. Analysis of the digital maps obtained suggests a free inflow of Ca2+ and Cd2+, in approximately equal amounts. Calcium-cadmium competition was revealed within the whole sample as well as in the zoomed fragments comprising ooplasm filled with yolk and trophocyte nucleolus.