Radioautographic studies on aging change of DNA synthesis and the ultrastructural development of mouse adrenal gland.
In this paper the DNA synthesis changes as well as ultrastructural aspects of the endocrine cells of the mouse adrenal gland from the 19th prenatal day until 2 years of life have been examined. The percentage of the labelled cells after injection of tritiated thymidine was maximal in the zona glomerulosa and in the medullaris at the 19th embryonic day whereas it was at the first postnatal day in the zonae fasciculata and reticularis, decreasing thereafter, reaching a low level on the 14th postnatal day. From the first month of life onwards, the labeling indices in both cortex and medullaris remained low, without significant differences in the different groups of age, but some regional differences. The number of labelled cells in the zona glomerulosa was higher than in both other cortex zones from the 19th embryonic day to the first day postpartum, whereas the labeling index (LI) was higher in the medullaris during the early postnatal period. At these embryonic and early postnatal periods the ultrastructural aspects appeared undeveloped, but abundant cell organelles like smooth endoplasmic reticulum, mitochondria with tubular or vesicular cristae and lipid inclusions could be observed in all three cortical zones, from two weeks onwards. A comparison has been attempted between the DNA synthesis and EM: the ultrastructural development.
Ito
M
M
Department of Anatomy and Cell Biology, Shinshu University School of Medicine, Matsumoto, Japan.
D000311:Adrenal Glands / Q000000981:diagnostic imaging / Q000196:embryology / Q000254:growth & development / Q000378:metabolism* / Q000648:ultrastructure; D000375:Aging / Q000235:genetics*; D000818:Animals; D001345:Autoradiography; D004247:DNA / Q000096:biosynthesis*; D051379:Mice; D008815:Mice, Inbred Strains; D008854:Microscopy, Electron; D011859:Radiography
D004247:DNA