Dexamethasone modulated protein synthesis in polymorphonuclear leukocytes: response in rheumatoid arthritis.

Reduced responses of PMNL polypeptide synthesis to glucocorticoid may allow the development of rheumatoid inflammation despite apparently adequate levels of endogenous corticosteroids.

Abstract

Nine polypeptides whose rate of synthesis is modulated in polymorphonuclear leukocytes (PMNL) by dexamethasone were studied by 2-dimensional polyacrylamide gel electrophoresis. In each case, there was a time lag between addition of dexamethasone and the appearance of any change in rate of synthesis. In PMNL from a group of patients with rheumatoid arthritis, dexamethasone modulated the synthesis of the same polypeptides as in PMNL from a group of healthy volunteers, but the degree of response of their polypeptides to dexamethasone was significantly reduced as measured by assaying the level of synthesis of a polypeptide of molecular weight 16,000. Reduced responses of PMNL polypeptide synthesis to glucocorticoid may allow the development of rheumatoid inflammation despite apparently adequate levels of endogenous corticosteroids.