Neonatal rats were injected with 6-hydroxydopamine (6-OHDA) for chemical sympa-thectomy. The rats were treated with restraint stress when they grew up to 56 d. It has been found that the generation of immunosuppressive protein of stress (ISPS) is significantly reduced, suggesting that peripheral sympathetic nerve plays an important role in mediating the generation of ISPS. Neonatal rats were injected with 6-hydroxydopamine (6-OHDA) for chemical sympa-thectomy. The rats were treated with restraint stress when they grew up to 56 d. It has been found that the generation of immunosuppressive protein of stress (ISPS) is significantly reduced, suggesting that peripheral sympathetic nerve plays an important role in mediating the generation of ISPS.