Ageing Associated Changes in Macromolecule Synthesis in the Endocrine Organs as Revealed by Microscopic Radioautography

The endocrine system of men and experimental animals consists of several endocrine organs. The term “Cell Ageing” initially means how the cells change due to their ageing. It contains 2 meanings, one how a cell changes when it is isolated from original animals or plants such as in vitro cells in cell culture, while the other means how all the cells of an animal or a plant changes in vivo due to the ageing of the individual animal or plant. I have been studying the latter changes from the viewpoint of the cell nutrients, the precursors for the macromolecular synthesis such as DNA, RNA, proteins, glucides and lipids, which are incorporated and synthesized into various cells of individual animals. Therefore, this article deals with only the cell ageing of animal cells in vivo, how the metabolism, i.e., incorporations and syntheses of respective nutrient precursors in various kinds of cells change due to the ageing of individual experimental animals such as mice and rats by means of microscopic radioautography to localize the RI-labeled precursors. The incorporations and syntheses of various precursors for macromolecules such as DNA, RNA, proteins, glucides, lipids and others in various kinds of cells of various organ in endocrine system are reviewed referring many original papers already published from our laboratory during these 50 years since the late 20C to the early 21C.