Relationship of memory behaviors and changes of synapse structure in vascular dementia rats / 第三军医大学学报

ABSTRACT

Objective To explore the relationship of the changes of memory behavior and the of changes of the parameter of synapse structure in the brain cortex and hippocampus of chronic cerebral hypoperfusion rats Methods Chronic cerebral hypoperfusion rat model was established by ligating bilateral common carotid arteries of the old rats (over 12 months) The rats were divided into 3 groups, normal, 2 months ischemia, and 4 months ischemia groups The memory behavior changes were observed with a computerized shuttle training case The ultrastucture of synapse were observed with electron microscopy for the number density, length of activity cord, area of synapses disk, surface density of the synapse, and the results were analyzed with stereology and image analyses The relationship between the behavior and the ultrastructure were studied Results Active avoidance response (AAR) and passive avoidance response (PAR) were decreased in the 2 months ischemia group and the 4 months ischemia group The number density (Nv) of the synapses in the brain cortex and hippocampus were reduced in the 2 months ischemia group and the 4 months ischemia group The length of activity cord (L), the area of synapses disk (S), the area density (Sv) in the hippocampus decreased in the 2 and 4 months ischemia group, and those in the brain cortex did not change in the 2 groups Conclusion The decrease of the number density (Nv) and the length of activity cord (L) of synapses in the chronic cerebral hypoperfusion is related to the memory behavior changes