[DNA synthesis and cell reproduction during hemopoiesis in the common frog in the course of spring under a varying temperature regimen].
The proliferation of grass frog hemocytoblasts and differentiation of various lines of hemopoiesis have been studied by means of repeated injections of 3H-thymidine during two spring months. The ability of population of hemocytoblasts to change the size of its proliferative pool is supposed to be regulated by the interaction of thermal and photoperiodical factors. The differentiation of separate lines of hemopoiesis begins in various seasons and depends, in various degrees, on the temperature. The neutrophil and thrombocyte lines are most labile, the erythroid line is most independent. Seasonal characters of erythropoiesis are discussed under comparative aspect.