THE INFLUENCE OF TUMOR GROWTH ON THE SYNTHESIS OF α2-AP (ACUTE PHASE) GLOBULIN OF RAT SERUM
The effects of growth of the Walker 256 carcinosarcoma on the α2-AP (acute phase) globulin, fibrinogen, seromucoid, and haptoglobin fractions of plasma were investigated in adult, male Sprague–Dawley rats in a longitudinal study. Early increases in α2-AP globulin and seromucoid levels were found to be related to the tissue injury associated with the implantation procedure. Significant elevations in the α2-AP globulin, fibrinogen, and seromucoid fractions coincided with the onset of progressive tumor growth. Serum haptoglobin concentrations exhibited a delayed rise. This was attributed to the in vivo formation of haptoglobin–hemoglobin complexes. It was suggested that the increases in all fractions reflected the release of humoral mediators from injured or necrotic cells wrhich stimulated increased synthesis of the fractions by the liver.