Abstract A program of study on DNA synthesis and mitosis in normal and injured tissues is being carried out in this laboratory. It has been demonstrated that injuries to the lens epithelium or corneal endothelium can stimulate the incorporation of tritium-labeled thymidine by many cells.1,2 The accumulated evidence from other studies has suggested that thymidine is a specific precursor to DNA synthesis and is incorporated into cells that are undergoing chromosome duplication in preparation for cell division.3,4 It is furthermore assumed that the tritium thus incorporated into cell nuclei is retained indefinitely by the cell5; a decrease in tritium per cell being accomplished, however, by subsequent cell divisions. Corneal endothelium apparently normally undergoes very little or no mitotic activity.6,10 For a limited period of time after mechanical injury, however, a number of cells in the vicinity of the wound show thymidine incorporation and division. After this period, References 1. Harding, C. V.; Donn, A., and Srinivasan, B. D.: Incorporation of Thymidine by Injured Lens Epithelium , Exp. Cell Res. 18:582-585, 1959.Crossref 2. Mills, N. L., and Donn, A.: Incorporation of Tritium-Labeled Thymidine by Rabbit Corneal Endothelium , A.M.A. Arch. Ophthal. 64:443-446, 1960.Crossref 3. Hughes, W. L.; Bond, V. P.; Brecher, G.; Cronkite, E. P.; Painter, R. B.; Quastler, H., and Sherman, F. G.: Cellular Proliferation in the Mouse as Revealed by Autoradiography with Tritiated Thymidine , Proc. Natl. Acad. Sci. 44: 476, 1958.Crossref 4. Taylor, J. H.; Woods, P. S., and Hughes, W. L.: The Organization and Duplication of Chromosomes As Revealed by Autoradiographic Studies Using Tritium-Labeled Thymidine , Proc. Nat. Acad. Sci. 43:122-128, 1957.Crossref 5. Leblond, C. P.; Messier, B., and Kopriwa, B.: Thymidine-H3 As a Tool for the Investigation of the Renewal of Cell Populations , Lab. Invest. 8:296-308, 1959. 6. Ballowitz, E.: Über das Epithel der Membrana elastica posterior des Auges, seine Kerne und eine merwürdige Struktur seiner grossen Zellsphären , Arch. Mikr. Anat. Entw. 56:230-291, 1900.Crossref 7. Cogan, D. G.: Applied Anatomy and Physiology of the Cornea , Trans. Amer. Acad. Ophthal. Otolaryng. 55:329-359, 1951. 8. Binder, R. F., and Binder, H. F.: Regenerative Processes in the Endothelium of the Cornea , A.M.A. Arch. Ophthal. 57:11-13, 1957.Crossref 9. Stocker, F. W.: The Endothelium of the Cornea and Its Clinical Implications , Trans. Amer. Ophthal. Soc. 51:669-786, 1953. 10. von Sallmann, L.: Experimental Studies of Some Ocular Effects of Alpha-Chymotrypsin , Trans. Amer. Acad. Ophthal. Otolaryng. 4:25-32, 1960. 11. Hughes, W. L.: The Metabolic Stability of Deoxyribonucleic Acid, The Kinetics of Cellular Proliferation , edited by F. Stohlman Jr., New York, Grune & Stratton, Inc., 1959, pp. 83-94.
Archives of Ophthalmology – American Medical Association
Published: Apr 1, 1961