THE SEQUENCE OF CHANGES IN BLOOD-FLOW AND LYMPHOCYTE INFLUX TO STIMULATED RAT LYMPH-NODES

Google Scholar
  • 1 January 1981
    • journal article
    • research article
    • Vol. 44  (1) , 125-133
Abstract
The rat popliteal lymph node was studied from 1 h to 8 days after the footpad injection of either sheep erythrocytes or syngeneic rat erythrocytes. The following were measured relative to the contralateral (unstimulated) lymph node: blood flow; lymph node weight; influx of lymphocytes from the blood; [3H]-thymidine incorporation; [35S]-sulfate incorporation into macromolecular form (chiefly by high endothelial venules). After the arrival of sheep erythrocytes all 5 quantities showed substantial increases which began in a definite sequence. The blood flow started to rise 1st and may have been the main factor contributing to the later increase in lymphocyte influx. Increased sulfate incorporation began later than the rise in lymphocyte influx. After the injection of rat erythrocytes a small increase in lymphocyte influx was found without a corresponding increase in blood flow. In rats irradiated before the footpad injections lymphocyte influx increased 3-fold after sheep erythrocytes, rat erythrocytes or PBS [phosphate-buffered saline], again without a corresponding increase in blood flow. While variation in blood flow to high endothelial venules is 1 important factor in determining the supply of lymphocytes to the lymph node other factors are operative in certain situations.