IMMUNOMODULATING AND ANTIINFLAMMATORY PROPERTIES OF THE SYMPATHOLYTICCOMPOUND 6-HYDROXYDOPAMINE

The objective of this study was to analyse the anti-inflammatory and i mmunosuppressive properties of 6-hydroxydopamine (6-OHDA), a well know n sympatholytic compound. Collagen type II arthritis, a T cell-depende nt autoimmune disease, was significantly suppressed by a short-term ad ministration of 6-OHDA at the time of the disease onset. Similar outco me was observed when in vivo models of T cell-dependent and independen t inflammatory reactions were applied. In contrast, long-term pretreat ment with 6-OHDA and hence efficient sympatholysis did neither affect the course of arthritis nor the outcome of T cell-dependent and indepe ndent inflammatory reactions. These findings, together with evidence o f dose-dependent in vitro inhibitory effects of 6-OHDA on lymphocyte p roliferation and differentiation, indicate that the anti-inflammatory features of this compound are mediated through a direct action on effe ctor cells rather than by sympatholysis.