Influence of some irritating or immunostimulating substances on experimental pleurisy in the rat.

Irritating substances, such as turpentine, carrageenan and a reticulo-endothelial system-activating immunostimulant (crude cell walls of Mycobacterium smegmatis), when administered parenterally, inhibit various types of experimental pleurisies. These anti-inflammatory properties may be related to the increase which they induce in serum and pleural exudate levels of haptoglobin and of oxidative activity towards paraphenylenediamine.