Abstract:

BACKGROUND: Previous studies have shown that cerebral selective profound hypothermia combined with antegrade cerebral perfusion can improve the resistance of monkeys to cerebral hypoxia-ischemia.
OBJECTIVE: To observe the effect of selective cerebral profound hypothermia on the ultrastructure and Vimentin expression of monkey hippocampi after severe cerebral ischemia.
METHODS: Eight healthy adult rhesus monkeys were randomly divided into two groups: profound hypothermia (n=5), and normothermia (n=3). For the monkeys in the profound hypothermia group, bilateral carotid arteries and jugular veins were occluded for 10 minutes at room temperature; Ringer’s solution at 4 ℃ was then perfused through the right internal carotid artery and flowed out of the right jugular vein, and the brain temperature remained below 18 ℃; 60 minutes later, the cerebral blood flow was restored. For the normothermia group, all procedures were the same except that the perfusion liquid was replaced with Ringer's solution at 37 ℃.
RESULTS AND CONCLUSION: All animals in the profound hypothermia group were successfully resuscitated. No significant abnormalities of the hippocampus morphology and ultrastructure were observed. In contrast, in the normothermia group, no monkeys were alive after perfusion, with abnormal hippocampus morphology and ultrastructure to different extents. Vimentin expression in the hippocampus was significantly lower in the profound hypothermia group than the normothermia group (P < 0.01). Selective cerebral profound hypothermia following 10-minute occlusion of the bilateral common carotid arteries could down-regulate Vimentin expression in the hippocampus and protect the hippocampus from severe cerebral ischemia.