Changes in tissue distribution of rat alpha 1-macroglobulin and pregnancy-associated alpha 1-glycoprotein after...

Antiserum against rat alpha 1-macroglobulin (alpha 1MG) was produced in rabbits. Antiserum against rat pregnancy-associated alpha 1-glycoprotein (PAG) was obtained by immunization with a partly purified PAG preparation and absorption of the serum with male rat serum. Acute inflammation was produced in non-pregnant female rats by a single intramuscular injection of turpentine. The concentrations of both macroglobulins in the serum and in tissue extracts were measured by rocket immunoelectrophoresis at various times up to 7 days after injury. Inflammation produced in the rats resulted in moderately elevated serum levels of these proteins soon after injury. At first, alpha 1MG levels in a number of tissues (heart, lung, kidney, spleen, pancreas, uterus and ovary) were depressed markedly; they then stabilized. The elevated serum concentrations of alpha 1MG remained unchanged during inflammation. The store of PAG in the tissues was rapidly depleted and its serum level decreased to a normal value 7 days after injury. Our findings indicate that alpha 1MG plays a more important role in maintenance of the proteinase inhibitory potential in the rat than does PAG.