[Structural organization of post-capillary venules in the somatic lymph nodes during total overheating of the body].

The structure of the postcapillary venules in the rat lymph nodes has been studied after a single total overheating at 43.5 degrees C. During the first three days an essential role is played by ultrastructural destructive processes, that demonstrate certain unfavourable states in cells. Nevertheless, the postcapillary venules perform their function quite satisfactory and even increase small lymphocytes transfer. The 7th-15th days are characterized with a steady compensation of the functional activity of these microvessels. By the 30th day some unfavourable changes in the endothelial ultrastructure are noted. This is, evidently, connected with a steady effect of the plasma toxic factor on the endothelium.