Regional blood flow to the lymph node during the immune response.

In 62 New Zealand white rabbits the regional blood flow to the popliteal lymph node was determined using the microsphere distribution and the Rb86C1 indicator methods. In 20 animals local immune response was induced with typhoid O antigen and in 7 with bovine serum albumin. The regional blood flow of the popliteal lymph node was 0.57 ml/gm/min. During the immune response the blood flow and weight changes were strictly proportional. The lymph node has the capacity to maintain its blood flow, even following significant enlargement.