The role of blood brain barrier in postoperative cognitive dysfunction of elderly mice / 复旦学报（医学版）

ABSTRACT

Objective To observe the changes of learning and memory ability in aged mice after appendectomy or isoflurane exposure and the permeability of blood brain barrier (BBB) in hippocampus in order to find the reasons for the destruction of BBB damgge.Methods Thirty C57BL mice (18-month) were randomly divided into 3 groupscontrol group (group C),surgery group (group S) and inhalation group (group Ⅰ).The permeability of BBB in hippocampus was detected with Evans-blue (EB) quantification.The alterations of tight junction protein were measured by occludin and claudin-5 using Western blot on the same day.The changes of two matrix metalloproteinases MMP-2 and MMP-9 were detected.Results Compared with the control group and inhalation group,surgery group had longer escape latencies and less platform crossings,and EB leaked into the hippocampus.The expression of occludin decreased,while the expressions of MMP-2 and MMP-9 increased.Conclusions MMP-2 and MMP-9 may cause the decrease of the expression of tight junction occludin protein,and lead to the destruction of BBB,which resultes in postoperative cognitive dysfunction.