Fish oil improves hemodynamic stabilization and inflammation after resuscitation in a rat model of hemorrhagic shock

Male SD rats (n = 48; 250~300 g) were randomly divided into 4 groups: SHAM, hemorrhagic shock (HS), hemorrhagic shock/resuscitation (HS/R) and fish oil (FO). Shock was induced, and a mean arterial pressure (MAP) was maintained at 35 to 40 mmHg for 60 minutes. Resuscitation was carried out by returning half of the shed blood and Ringer's lactate solution to the animal. In FO group, fish oil (0.2 g/Kg) was infused through caudal vena at 30 minutes after shock. Half of each group was killed at 30 minutes and at 4 hours after resuscitation. Then several kinds of inflammation and oxidative stress indicators such as IL-6, MPO and GSH were tested.FO group required less resuscitative fluid and had higher urinary output at the recovery periods from hemorrhagic shock than HS/R group(p < 0.001). After resuscitation, the MAP of HS/R group markedly declined than FO group (p < 0.001). The inflammatory indexes of FO group were lower than HS group and HS/R group and the same as sham group. But the level of endotoxin in FO group was significantly higher than sham group at 4 hours.Fish oil pretreatment before fluid resuscitation showed a beneficial effect to the hemodynamic stabilization and inflammation reduction in HS/R rat model.Hemorrhagic shock (HS) remains a major cause of death in both civilian and combat traumatic injury[1]. It followed by resuscitation is considered as an insult frequently induces a systemic inflammatory response syndrome (SIRS) that results in multiple-organ dysfunction syndrome (MODS)[2], which is a major clinical problem. HS represents the acute hypovolemia and hemodynamic derangement and the mechanism is recognized to be the increasing of reactive oxygen species generation, and endothelial activation after supplementation with ambient oxygen in a prior ischemic field, and inducing many systemic inflammatory factor released[3-5].Fish oil as pharmacological nutrients could directly and indirectly decreasing the production of inflammatory eicosanoids, cytok