Effects Of Buchang Naoxintong On Cognition And Apoptosis Of Cranial Nerve Cell In Vascular Dementia Rats Induced By Chronic Ischemia

With the arrival of aging coen, the incidence of dementia is increasing. In Asia, VD is the most common type. VD is an impairment of cognitive function of caused by cerebrovascular disease. Because VD is somewhat reversible, so we want to interfere it in the nonage of the infarction, and to examine the way of delay the progression of dementia.Recently,some researches raised that apoptosis of nerve cells had a close relationship with cranial ischemia. The gene of Bcl-2 have vital function in apoptosis.So far it is the most important antergic gene.Buchangnaoxintong is made from milkvetch root, sanguisuge, angle worm and so on, traditional medicine presume that it can promote the blood circulation. There are essays validate that this Chinese patent medicine can increase cerebral blood flow (BF) decrease cerebral vascular resistance (CVR) apparently, and also can prolong the clotting time (CT), commonly used in the treatment of ischemic cerebrovascular disease, but if it also can prevent the progressive impairment of cognitive function is seldom reported. So we want to examine the value of this medicine in the prevention of VD according to the observe the influence of this medicine to the ethology, pathology ,the change of Bcl-2 and apoptosis of the nerve cells in the white matter of the vascular dementia rats induced by chronic cerebral ischemia.This study Choose healthy male Wistar rats of 3-5 monthes, divided them into 3 groups randomly as control group, operated group and treated group, the VD rat models after chronic cerebral hypoperfusion are established by permanent bilateral common carotid arteries occlusion and the treated group are lavaged with Buchangnaoxintong after the operation. Morris water maze experiment is adopted to test the rat's memory change of each group, the escape incubation period expressed the rat's memory ability. Brain samples with HE staining and Tunel staining from hippocampus are observed with light microscopic methods. The changes of Bcl-2 by the immunohistochemical methods are observed.The result and analysis are followed: 1. Behavioral changes: We take the escape incubation period of MWM as the evaluation target. Compared with control group, the treated group and the operated group's escape incubation period is longer (P<0.01); compared with the operated group, the treated group 's escape incubation period is shorter (P<0.01). Compared with other ischemic models, this memory dysfunction induced by the occlusion of bilateral carotid arteries is more chronic and more permanent and we concluded from the results in Morris water maze tests that chronic hypoperfusion could result in chronic and permanent cognitive impairment. And we also can draw the conclusion that Buchangnaoxintong can relieve the degree ofcognitive impairment. 2. Pathological changes of neuron: In the control group, the degeneration and detachment of neuron could be seen, so did the necrosis of the neurons and hypertrophic glia. We thought these pathological changes were due to the chronic and steady reduction of CBF, but not by the acute cerebral ischemia. But the ischemic changes of the treated group are relieved apparently. 3. Immunohistochemical changes and apoptotic rate of never cells: The Bcl-2 protein expression in the rats treated with Buchang Naoxintong was more than that in model group at different time (P<0.05). The apoptotic rate of never cells in rats in drug group was lower than that in model group(P<0.05). So we can draw the conclusion that Buchang Naoxintong can increase the expression the Bcl-2 protein,restrain apoptosis of the cranial nerve cells.In a word, the conclusions we can draw are followed: 1. Permanent bilateral common carotid arteries occlusion to the rats can lead to ischemic damage of the neuron and apoptosis. 2. Permanent bilateral common carotid arteries occlusion to the rats can lead to chronic and permanent cognitive impairment. 3. Buchang Naoxintong can relieve the cognitive impairment caused by chronic ischemia.4. Buchang Naoxintong can increase the expression the Bcl-2 protein,restrain apoptosis of the cranial nerve cells in rats. 5.One of the mechiems that Buchang Naoxintong can relieve the cognitive impairment may be restrain apoptpsis.