Modified bilateral carotid artery ligation to establish a vascular dementia rat model and investigate changes in cerebral blood flow and effects on angiogenesis-related proteins / 中国实验动物学报

ABSTRACT

Objective Apply modified bilateral carotid artery ligation to establish a VD rat model to observe changes in cerebral blood flow and expression of angiogenic proteins.Methods Thirty-six SD male rats were randomly divided into a sham group(n = 18)and model group(n = 18).In the sham group,only the bilateral carotid artery was isolated without ligation,whereas in the model group,the bilateral carotid artery was ligated to establish the VD model.The Morris water maze behavior test was applied before and 14 days after modeling.Variation in cerebral blood flow was detected by laser speckle contrast imaging.Protein expression of HIF-1α,VEGF,and HO-1 was detected by Western Blot.IL-4 and IL-10 contents were measured by ELISA.Results At 14 days after modeling,escape latency was significantly prolonged and the frequency of crossing the platform had significantly decreased in the model group compared with the sham group(P<0.05).At 2 hours,3 days,and 7 days after modeling,cerebral blood flow in the model group was significantly lower than that in the sham group(P<0.05).At 14 and 21 days after modeling,no significant difference was found in cerebral blood flow between sham and model groups(P>0.05).In the model group,cerebral blood flow was decreased to a minimum at 2 hours after modeling(P<0.05)and then began to recover.The peak of recovery occurred at 3～7 days after modeling and returned to the level before modeling on day 14 after modeling.At postoperative day 21,expression of HIF-1α,VEGF,and HO-1 proteins in the hippocampus of the model group was increased remarkably(P<0.05)and the serum contents of IL-4 and IL-10 in the model group were significantly increased compared with those in the sham group(P<0.05).Conclusions The variation in cerebral blood flow in the VD rat model established by the modified bilateral carotid artery ligation was dependent on time.At postoperative day 21,HIF-1α,VEGF,and HO-1 in the hippocampus were increased significantly,which was accompanied by increased levels of IL-4 and IL-10.