X-ray microanalysis of inner ear fluids in the embryonic and newborn guinea pig

Summary

In energy-dispersive histograms, changes in the relative peak intensities were followed, especially Cl and K, which indicate the maturation of endolymph. The maturation of endolymph in the guinea pig occurs prior to birth. In X-ray histograms, distinct peaks for Cl and K, but also for Na, were observed approximately 20 days before birth (DBB). The lesser relative peak intensities for Cl and K as compared with mature endolymph indicate an immature endolymph composition at this stage of development. The relative peak intensities of Cl and K increased at approximately the 10-DBB stage and showed similar values as at birth.