Calcium content and concretions of pineal glands of young and old rats. A scanning and X-ray microanalytical study.

Calcium content and pineal concretions were studied in young (2-3 months) and old (28 months) Wistar rats. Samples, deep-frozen by liquid propane isopentane and freeze-dried were analysed by means of X-ray microanalysis in a scanning electron microscope. Total semi-quantitative measurements revealed that pineals of old rats showed a marked increase of calcium compared with the pineals of young rats. It is thus suggested that a calcium-rich environment is responsible for the growth of pineal concretions, which only appear in old rats. Pineal calcifications in rats could thus be an indicator of aging and/or of a degenerating state.