Patients who have had a stroke have a higher prevalence of dementia associated with functional handicap affecting the quality of life and creating a loss of autonomy. My work aims to develop a long term model of stroke in rat to identify cerebral lesions and the associated behavior deficits as well as the involved cellular mechanisms. Male Wistar rats undergo transient ischemia/reperfusion. MRI was performed at 24 hours, 7 days, 1, 2, 4 and 6 months after operation. In parallel, behavioral tests were assessed to follow motor and mnesic functions. After sacrifice, brains are removed to made histological and molecular studies. Motor and mnesic deficits appeared during our study. MRI studies showed that lesion differentiated at 7 days of reperfusion and T2-MRI evidenced atrophies appearing since 1 month post-ischemia in entorhinal cortex and hippocampus. Histological studies evidenced a decreased cellular surface in hippocampal regions associated to a decreased expression of the neurotrophic factor BDNF which could explain atrophies. These results proved that this long-term ischemic model in rat is a good one to induce behavioral deficits like functional problems appearing at distance in post-stroke patients.
