Studies on the nature of the seromucoid and haptoglobin responses to experimental inflammation

The effects of the administration of actinomycin D, ethionine, and puromycin on the elevations of the total seromucoid fraction and of one of its components (haptoglobin) occurring during experimental inflammation have been studied. All three inhibitors of protein synthesis abolished the elevation of haptoglobin level. Ethionine and puromycin also completely suppressed the elevation of total seromucoid level, whereas actinomycin D only partially suppressed it. The seromucoid and haptoglobin levels in control animals injected with only the inhibitors of protein synthesis were not in general significantly different from those of the animals injected with turpentine and these agents. The results are consistent with the concept that the elevation of various plasma glycoproteins occurring during inflammation is principally due to de novo synthesis of these proteins rather than release of preformed proteins from tissue pools.