[Effect of cytostatic drugs on fever development following administration of bacterial pyrogen]

A study was made of the development of pyretic reaction to the administration of a bacterial lipopolysaccharide (pyrogenal) after preliminary treatment of rabbits with actinomycin D and cortisone. Such treatment failed to change the reactivity of thermoregulating centres to the endogenous pyrogen. Intravenous injection of bacterial pyrogen was followed by marked shortening of pyretic reaction; the reaction was markedly inhibited in response to its intracysternal administration. An important role played by polymorphonuclear leukocytes in the formation of endogenous pyrogens in the mechanism of pyrexia induced by bacterial pyrogens was shown in this work.