[Mitotic behaviour and proliferation metabolism in allogenic kidney transplants of the rat, in the first 6 days afer recirculation (author's transl)].

Comparative experiments were carried out on 41 allogenic kidney transplants of the rat to determine the mitotic behaviour and proliferation metabolism (application of H3 thymidine) in the first 6 days after recirculation. 3 days after transplantation DNA synthesis in the epithelium of cortex and medulla reached its peak. After this time the H3 labelling index for these cell nuclei dropped until on the 6th day, it had a value equivalent to that of the first day. The estimation of the decline of DNA synthesis in the epithelial cell nuclei and the increase of the lymphocyte proliferation in the interstitial tissue of cortex and medulla of the transplants from the 4th day on are signs of rapidly advancing transplant rejection. The changes in proliferation metabolism of the epithelial cell nuclei precede the mitotic changes by a few hours. The transplant changes caused by primary postischemic and secondary tissue rejection can be made comprehensible by the determination of the average cell density of H3 labelled cortex, medulla and epithelial cells.