Abstract： Objective To investigate protective effects of intravenous perfluorocarbon emulsion (PFCE) on decompression sickness (DCS) in rats.Methods An animal model was developed by using adult SD rats with the "700 kPa-60 min hyperbaric air exposure and 3 min decompression" profile.The animals were administered PFCE (7 ml/kg) intravenously immediately before compression(n=20) or after decompression (n=23).Animal behavior (including morbidity and mortality) and other symptomatic and pathologic indices were studied.The animal groups with saline (n=20) or no treatment(n=21) following exposure were used as control.Results Morbidity for the animals treated with PFCE (21.7%) was significantly lower than those treated simply with saline (60.0%)(P<0.05) or without treatment (66.7%)(P<0.01).When compared with that of the control group (42.9%),the mortality of PFCE animals (13.0%) was significantly lower (P<0.05).Most symptomatic and pathologic parameters improved notably (P<0.05).No significant differences could be seen in the morbidity (80.0%) and mortality (45.0%) of the animals treated with PFCE before compression,when a comparison was made between the PFCE treatment group and the saline or the control group (P>0.05).Conclusions Immediate intravenous administration of PFCE following hyperbaric exposure had obvious preventive and therapeutic effects on the occurrence of acute DCS.