Dendritic growth and retraction are important hallmarks of neuronal growth and injury respectively. It is therefore important to elucidate the regulators of dendritic growth. Previous studies have shown that a family of proteins known as Bone morphogenetic proteins (BMPs) promote dendritic growth in sympathetic neurons and enhance dendritic outgrowth in central neurons. In this study, we identified free radical mediated signaling as potential regulator of dendritic growth in sympathetic neurons. Cultured sympathetic neurons from E21 rat pups were treated with BMP-7 (5 ng/ml or 50 ng/ml), with or without antioxidants. Some of the antioxidants examined in this study include Diphenylene iodinium (DPI), Nordihydroguiaretic acid (NGA), Vitamin C, Vitamin E, and Desferroxamine (DFO). Our results showed that BMP-7 induced dendritic growth was inhibited by antioxidants in a dose dependent manner, without affecting axonal growth or cell numbers. Furthermore, DPI and DFO induced dendritic retraction whereas NGA prevented further growth of existing dendrites. These results suggest that low levels of free radicals are beneficial for maintenance of dendrites in sympathetic neurons. We are currently exploring the possible connections between BMP signaling and free radical signaling in sympathetic neurons. (Supported by the Saint Mary’s College Summer Research Program)