Kinetics of mononuclear phagocytes after thymectomy

Some kinetic parameters of mononuclear phagocytes have been studied. Wistar rats were injected with 3H-thymidine. Samples of peripheral blood and peritoneal macrophages were obtained at 12, 14, 24, 36, 48, 60, and 84 hours respectively after injection. The labelling index and the mean grain count were determined. The turnover of monocytes was slowed down in the thymectomized animals. It is assumed that thymectomy had changed some biological qualities of mononuclear phagocytes and/or the humoral relations connected with the function and the regulation of mononuclear phagocytes.