Prostaglandins: Biphasic dose responses

Biphasic dose responses induced by prostaglandins are documented and assess ed with respect to quantitative features of their dose-response functions, mechanistic foundation, and biological generalizability. Biphasic responses were seen for multiple endpoints, including DNA synthesis, neutrophil migr ation, corticosterone production, fibroblast proliferation, and other param eters. In addition, numerous nonsteroidal antiinflammatory agents and other drugs alter prostaglandin concentrations and/or transport in a biphasic do se-response manner. These findings have considerable implications for the u nderstanding of basic biological regulatory processes as well as clinical p ractices.