Light and Electron Microscopic Radioautographic Studies on the Cell Aging of the Neuro-Sensory System of Mice

Abstract

The term “Cell Aging” initially means how the cells change due to their aging. However, there are 2 meanings in this term, i.e., how a cell changes when it is isolated from original animals or plants such as in vitro cells in cell culture, otherwise how all the cells of an animal or a plant change in vivo due to the aging of the individual animal or plant. We first studied 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 aging 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 aging of individual experimental animals 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. This review deals with the results of neuro-sensory system of mice only, i.e., the nervous system such as the brain, the spinal cord and the peripheral nerves as well as the sensory organs such as the eyes and the skin referring many original papers already published from our laboratory during these 60 years since the late 20C to early 21C.