Glucocorticoids induce the formation and release of anti-inflammatory and anti-phospholipase proteins into the peritoneal cavity of the rat.

1 Dexamethasone and hydrocortisone induced the release of anti-phospholipase proteins into the peritoneal cavities of rats. 2 Adrenocorticotrophic hormone (ACTH) also releases these proteins in normal but not in adrenalectomized rats. 3 Peritoneal lavage proteins were separated by ion-exchange and size exclusion chromatography. The anti-phospholipase activity occurred in four separate fractions with the major component having an apparent mol. wt. of 40 k. 4 Column fractions containing these anti-phospholipase proteins had anti-inflammatory effects in the rat carrageenin pleurisy model whereas other fractions were inactive. 5 The proteins appear to be identical to macrocortin and lipomodulin, the 'second messengers' of glucocorticoid hormone action on the arachidonate system.