Degradative pathways in cultured synovial fibroblasts: selective effects of pulsed electromagnetic fields

A cell culture model for studying the cytokine-mediated degradation of connective tissue was exposed to clinically applied, low-frequency pulsed electromagnetic fields (PEMF), and levels of collagenolytic activity, two lysosomal hydrolases, and prostaglandin E2 were measured. PEMFs reduced the release of two lysosomal enzymes by cultured rabbit synovial fibroblasts but did not affect their response to mononuclear-cell-conditioned medium. PEMF did not alter levels of cytokine activity produced by a mixed mononuclear cell population, nor did they affect the cytokine-mediated release of collagenase or prostaglandin E2 by synovial fibroblasts. The relevance of these findings to the clinical application of PEMF to soft- and hard-tissue injuries is discussed.