| Objective:Establishing a rational animal model was the basis of experimental study,it’s important to discuss the mechanisms of disease and assess the efficacy of drug interventions.Renal deficiency and blood stasis syndrome was the most common syndrome type in patients with vascular dementia（VD）.However,there is still no ideal animal model of vascular dementia with renal deficiency and blood stasis syndrome.In this study,Two-vessel occlusion（2-VO）was used in aged rats to establish an animal model combining renal deficiency and blood stasis with VD disease.The model was evaluated by observing the changes of animal physical signs,histopathology and serology.Method:SD male rats aged 52 weeks were randomly divided into 8 high age sham operation groups（HASOG）,8 high age model groups（HAMG）.SD male rats aged 8 weeks were randomly divided into 8 low age sham operation groups（LASOG）,8 low age model groups（LAMG）.In the process of modeling and after modeling,the dead rats were timely supplemented to maintain 8 rats in each group,and 8 rats in each group were finally included in the statistics.The rats in the two model groups were modeled using 2-VO method,the bilateral common carotid arteries of two sham groups were separated but not ligated.After modeling,the rats in each group were tested by Morris water maze;the physical signs,reproductive function and hippocampal pathological morphology of rats were observed;the hemarheology,nitric oxide（NO）,endothelin-1（ET-1）,testosterone（T）,estradiol（E2）,calcium（Ca）,phosphorus（P）,bone gla protein（BGP）were detected.Results:1.Changes in rat physical signsCompared to other 3 groups,the weight of HAMG rats increased slowly;the HAMG rats presented a series of features,including squinting,decreased autonomic activity,prone to lying down,slow action,slow reaction,less aggressive behavior,curled up on the waist and back,gregarious,the body hair is dry,thin,dull or yellowish,its tail has different degree of purple or yellow-brown spot,the tongue was dark purple and decrease in diet volume.2.Observation rat Morris water maze and the histopathology morphology of the hippocampus in the brain.Compared to the LASOG group,the escape latency of the LAMG rats was prolonged（P<0.05）;the number of through platfrom and the activity time in platfrom were reduced in both the LAMG and the LASOG group（P<0.05 or P<0.01）.Compared to the HAMG group,the escape latency in other3 groups were reduced,the number of through platfrom and the activity time in platfrom in other 3 groups were increased（P<0.05 or P<0.01）.Compared with the sham groups,the histopathological morphological change in the hippocampus of the model groups were all ischemic,but the histopathological change in the hippocampus of the HAMG were more significant.3.Comparison of reproductive function,E2,T,Ca,P and BGP levels among different groupsCompared to the LASOG,the number of births and T of the LAMG rats was reduced（P<0.05 or P<0.01）;the testis index、number of births and T were reduced in the HASOG（P<0.01）.Compared to the HAMG,the number of pregnant female rats、testis index、the number of births、E2、T、Ca、BGP were increased and P reduced in the LASOG（P<0.05 or P<0.01）;the number of births、testis index、T were increased in the LAMG（P<0.01）;the levels of Ca and BGP were increased and P reduced in the LASOG（P<0.05）.4.Comparison of hemarheology,NO and ET-1 levels among different groupsCompared to the LASOG,the whole blood and plasma reduced viscosity（low/middle）、aggregation index、ET-1 were increased and NO was reduced in the LAMG（P<0.05 or P<0.01）;the level of ET-1 was increased and NO was reduced in the HASOG（P<0.05）.Compared to the HAMG,the whole blood and plasma reduced viscosity（low/middle/high）、aggregation index、ET-1 were reduced and NO was increased in both the LASOG and the HASOG（P<0.05 or P<0.01）;the level of ET-1 was reduced and NO was increased in the LAMG（P<0.05）.Conclusions:1.2-VO method can cause ischemic changes in the hippocampal area of rats and decreased cognitive and learning memory ability of rats,which conforms to the VD disease model.2.Compared to other groups,the high age model rats made by 2-VO method have the characteristics of body hair dullness,the tongue was dark purple and its tail has different degree of purple or yellow-brown spot and so on.At the same time,the blood vessels showed hypercoagulability and hyperviscosity,which is consistent with the characteristics of TCM syndrome of blood stasis blocking collaterals.3.Compare to other groups,the high age model rats made by the method of 2-VO have the characteristics of slow weight growth,reduced autonomic activity,prone to lying down,curled up on the waist and back,thin body hair and poor memory,etc.At the same time,the number of pregnant females,number of births and testis index decreased,HPAT axis dysfunction and abnormal bone metabolism,which were consistent with the characteristics of renal essence deficiency syndrome with low renal bone and reproductive function in TCM.4.Compare to other groups,the high age model rats prepared by 2-VO method were most consistent with the clinical characteristics of VD with renal deficiency and blood stasis syndrome. |
