THE EFFECT OF A DELAYED CHRONIC DTPA TREATMENT ON THE PU MICRODISTRIBUTION IN RAT BONE - PRELIMINARY-RESULTS USING HEMI-BLOCKS OF FEMURS

We have developed a combined autoradiographic and confocal microscope analysis to visualize the decorporation of Pu in bone after delayed an d chronic DTPA treatment using hemi-blocks of femurs. Pu-238-citrate w as administered to rats by intravenous injection at 21 weeks of age. T reatment by adding Zn-DTPA (1 mM) to the drinking water for one month was performed at 42 and at 85 days after contamination. Bone decorpora tion was estimated at 10-15% and at 5-7% at the end of the first and t he second treatment, respectively. Because the block thickness was lar ger than the range of a particles in the tissue (25-30 mu m), quantita tive a track recording can be performed with a spatial resolution of l ess than 60 mu m. The autoradiographs were compared with confocal imag es of the hemi-femur block surface so that the different bone compartm ents could be easily identified. With this method a clear preferential decorporation of bone surfaces was visualized compared to controls. ( C) 1998 Elsevier Science S.A.