Recruitment of neutrophils across the blood-brain barrier. The role of posttraumatic hepatic ischemia1

Purpose: To study the effects of total hepatic ischemia, and reperfusion on the accumulation of neutrophils in the brain of rats submitted to normovolemic conditions as well as to controlled hemorrhagic shock state. Methods: Thirty two adult male Wistar rats, were divided into four groups: the Control group, was submitted to the standard procedures for a period of 60 min of observation; Shock group, was submitted to controlled hemorrhagic shock (mean arterial blood pressure=40mmHg, 20min) followed by volemic resuscitation (lactated Ringer’s solution + blood, 3:1) and reperfusion for 60min; Pringle group, was submitted to total hepatic ischemia for 15min and reperfusion for 60min. The total group was submitted to controlled hemorrhagic shock for 20min followed by volemic resuscitation (lactated Ringer’s solution + blood, 3:1), total hepatic ischemia for 15min and reperfusion for 60min. Measurements of serum lactate and base excess were used to characterize the hemorrhagic shock state with low tissue perfusion. The counting of neutrophils on the brain was performed after the euthanasia of animals. Results: The values for the counting of neutrophils on the brain indicate that did not occur difference among studied groups (p=0.196) (Control 0.12±0.11, Shock 0.12±0.13, Pringle 0.02±0.04, Total 0.14±0.16). Conclusion: Hemorrhagic shock associated to total hepatic ischemia for 15 minutes, followed by 60 minutes of reperfusion, did not causes significant neutrophils accumulation in the brain of rats.