Studies on the Reactivity of Lymph Node. The Influence of Antigenic Stimulation upon the Blood Vascular Architecture of Lymph Node

The influence of antigenie stimulation upon the blood vascular architecture of the popliteal lymph node in the rat and rabbit was studied by the injection method, after injecting either sheep blood or complete Freund's adjuvant into the footpad of a hind leg. The popliteal nodes on the opposite side remained unstimulated and served as controls. Chief findings are as follows. 1. After antigenic stimulation many areas undergoing hyperplasia appear in the cortex of the stimulated nodes. 2. Such areas are characterized by scanty and coarse vascular mesches and much greater caliber of the blood vessels than in other areas. 3. In the areas which are not undergoing hyperplasia, the meshes of blood vessels are very fine and the caliber of such blood vessels are much smaller than in the areas undergoing hyperplasia,