ELECTRON-PROBE X-RAY-MICROANALYSIS OF THE ELEMENTAL COMPOSITION OF THE PINEAL-GLAND OF YOUNG-ADULTS AND AGED RATS

Fractures of deep-frozen and freeze-dried pineal glands were analysed for elemental composition by means of X-ray microanalysis with a scann ing electron microscope. The results from young adults (3 months old) were compared with those from aged animals (24 months old); significan t increases in S, Ca, Al, Si, and Fe were observed in aged animals whe n compared to young adults. There were no significant differences with Na, Mg, Cl, K, Ti, Cr, Mn, Ni, Cu, Zn, whereas a decrease of P was ob served in aged animals when compared to young adults. Whether the chan ges observed in elemental composition have a direct effect on the acti vity and production of metalloenzymes and the overall physiology of th e pineal gland are discussed.