Journal of Cell Science, Vol 3, 89-93, Copyright © 1968 by Company of Biologists

Submitted on August 19, 1967

Duration of Availability of Tritiated Thymidine Following Intraperitoneal Injection

¹ Department of Pathology, St Mary's Hospital Medical School London, W.2

Much indirect evidence supports the assumption that tritiated thymidine does not label cells which enter the deoxyribonucleic acid synthesis phase (S) more than 1 h after injection. Direct evidence confirming this assumption was obtained by counting labelled epithelial nuclei in mice killed 1, 4 or 6 h after a single intraperitoneal injection of [³H]thymidine; colchicine was used to prevent the increase in number of labelled nuclei which would otherwise have occurred because of cell division. The proportion of cells labelled was the same at 1 h as at 4 or 6 h after injection of [³H]thymidine. Nuclei were regarded as labelled if they were overlaid by 4 grains or more; comparison of nuclear and background labelling indicated that nuclei overlaid by 3 grains or less represented background labelling.

This article has been cited by other articles:

				S. Acklin and D van der Kooy Clonal heterogeneity in the germinal zone of the developing rat telencephalon Development, January 5, 1993; 118(1): 175 - 192. [Abstract] [PDF]