The response to thermal injury is a complex physiologic process requiring communication between sites of injury and distant target organs. The liver, one of these target organs, synthesizes a family of secretory proteins, the acute phase proteins, that carries out specific immunoprotective functions. In this study we investigated the effects of daily recombinant human interleukin-1alpha (rhIL-1alpha) administration on the serum levels of negatively regulated, i.e., albumin and Gc-globulin and positively regulated, i.e., alpha1-antitrypsin, acute phase proteins in a murine model of thermal injury. Adult CF-1 female mice underwent a 6.5-seconds, 20% total burn surface area, full thickness steam injury, and received either intraperitoneal rhIL-1alpha (20 microg x kg(-1) x day(-1)) or diluent for 10 days. Seven and 14 days after injury, mice were sacrificed, and serum albumin, Gc-globulin and alpha1-antitrypsin levels were measured by crossed immunoelectrophoresis technique. Thermal injury significantly lowered serum albumin levels, tended to decrease Gc-globulin levels, and increased serum alpha1-antitrypsin levels. Daily rhIL-1alpha administration after burn injury prevented hypoalbuminemia, and increased serum levels of Gc-globulin and alpha1-antitrypsin. IL-1 therapy might be helpful to maintain the homeostasis and immunity of the host after thermal injury.