The Effects of Occlusion of the Blood Supply to the Popliteal Lymph Node of the Rabbit on the Cell and Protein Content of the Lymph and on the Histology of the Node

Summary The anatomical arrangement of the blood vessels supplying the popliteal lymph node of the rabbit was determined by injecting latex into the femoral artery and vein. Complete occlusion of its blood supply caused no appreciable change in the flow and protein concentration in afferent and efferent lymph of the node. The cell count in the efferent lymph fell from 6th hr. to 5th day after occlusion to levels approaching those in afferent lymph, and during this time degeneration of cells within the node occurred except for small areas adjacent to the marginal and medullary sinuses. Regeneration of the lymphatic tissue with an increase in the cell counts of the efferent lymph began from about the 7th day after occlusion and was due to the regeneration of blood vessels connected with the blood circulation outside the node. In experiments, in which one or more small collateral arteries were left intact, no degeneration of the cells or reduction in cell content of the lymph occurred.