Figure 1. Dose–response for rapid radiation-induced reduction of endothelial cell numbers and the effect of prior administration of Hoechst 33342. Endothelial cell numbers were scored 24 h after irradiation, as described in the text. Some mice were injected intravenously with Hoechst 33342 10 min prior to irradiation (
) while the controls (•) were exposed to radiation only. Data points are mean cell counts for each group of mice. Standard errors are also shown (bars). The lines (—, protected fit; --, control fit) indicate the results of non-linear regression analysis using Equation (1) (see text and Table 1 for details).
