A New Model Of Alzheimer’s Disease

Alzheimer’s disease (AD) which described by a German psychiatrist and neuropathologist named Alois·Alzheimer firstly in1906is a central nervous system degenerative diseases. It is one of the most common causes of cognitive impairment in the elderly, the prevalence rate was5%to10%in the elderly over65years old, and which was more than50%in the elderly over85years old. Memory loss and cognitive impairment were shown in patients. AD has been one of the most costly diseases to society.In recent years, the incidence of Alzheimer’s disease showed an increasing trend. There is no cure because of the complex pathogenesis. To study the mechanism of Alzheimer’s disease and seek the effective treatment have been the focus of research. Recent research shows that Alzheimer’s disease and inflammation interrelate closely, the immune responses of microglia activation is a key to course of disease of AD and P-amyloid deposition and formation of senile plaques associate with inflammation. But there is few of AD models that caused by immune response in the brain. As the LPS intracerebral injection model is unsatisfactory. So we used2,4-dinitrochlorobenzene (DNCB) systemic sensitization and intracerebroventricular injection attacks to produce inflammation. Study the changes of behavior and pathology to discuss the mechanism about delayed-type hypersensitivity (DTH) caused AD model. And provide an effective treatment of AD.Objective:According to the immunological mechanisms of Alzheimer’s disease, by the method of inducing by DNCB and lateral ventricle attacked copy the model of AD.Methods:the mice were systemic sensitization and Morris water maze was used. After training, DNCB was intracerebroventricular injection. Then navigation test, spatial probe test, spontaneous activity experiments behavioral experiments were used to study the changes of behavior. Finally, the thymus index, spleen index, the cerebral index and water content of brain were measured, and HE (hematoxylin and eosin) staining were used to observe the pathological changes.Result:DNCB could successfully cause systemic sensitization and delayed-type allergic reactions after the attack, the body weight and the thymus index, spleen index were increased. The auricular attacks can cause significant ear swelling. Brain attack can lead to specific cognitive impairment and brain damage. Morris water maze navigation test latency was prolonged, the spatial probe test in the platform quadrant dwell time significantly reduced. At the same time the number of spontaneous activity has been reduced. Brain inflammatory edema, cerebral index and brain water content was significantly increased. Pathology revealed the damage of the pyramidal cells of the hippocampus and brain microglia activation.Conclusion:According to the immunological mechanisms of AD, by the method of inducing by DNCB and lateral ventricle attacked could copy the model of AD:This kind of model could successfully simulate both of the pathological changes in the brain and the behavioral characteristics of Alzheimer’s disease.