Changes in blood-cerebrospinal fluid barrier in postoperative delirium rats / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the changes in the blood-cerebrospinal fluid barrier in postoperative delirium rats.Methods:One hundred and forty-seven healthy female Sprague-Dawley rats, aged 3 months, weighing 240-300 g, were divided into 3 groups ( n=49 each) using a random number table method: control group (group C), anesthesia group (group A) and postoperative delirium group (group P). Group C received no treatment.Group A received 2-h anesthesia with 1.4% isoflurane.Group S underwent an exploratory laparotomy under 1.4% isoflurane anesthesia.The behaviors of rats in each group were tested at 24 h before surgery and 6, 9 and 24 h after surgery using buried food test, open field test and Y maze test.Sodium fluorescence was injected through the tail vein at 6, 9 and 24 h after surgery.Then the rats were sacrificed, the choroid plexus (CP) was obtained, and cerebrospinal fluid (CSF) of bilateral cerebral ventricles was collected, and the expression of ZO-1, occludin, claudin1, E-cadherin and VE-cadherin in CP was detected using Western blot.FITC-dextran 10, 40 and 70 kDa was injected through the tail vein at 6 h after surgery, and then CSF was collected for determination of the concentrations of NaFI, 10, 40 and 70 kDa fluorescein isothiocyanate labeled dextran (FITC-dextran) in CSF by fluorescence spectrophotometry.CP was obtained to observe the morphology of choroid plexus epithelial cells (CPECs) of bilateral cerebral ventricles with a transmission electron microscope. Results:Compared with group C and group A, the latency to eat food in buried food test was significantly prolonged, the time of staying at the central region was shortened, the percentage of the number of entries into novel arm and percentage of time of staying at novel arm in Y maze test were decreased, the freezing time in open field test was shortened, the expression of ZO-1, occludin and claudin1 in CP was down-regulated, the concentrations of NaFI and 10 kDa and 40 kDa FITC-dextranin CSF were increased ( P<0.05 or 0.01), the CPECs arranged at random and loose, the microvilli of CPECs were absent, the tight junction was blurred, and the gap became wider in group P. Conclusion:The occurrence of postoperative delirium is related to the change in blood-cerebrospinal fluid barrier.