RESUMEN
Objective To observe the effect of electroacupuncture at Baihui (GV20) and Shenting (GV24) on learning-memory function and ultrastructure in hippocampal CA1 region of rats after cerebral ischmeia-reperfusion. Methods A total of 25 male Sprague-Dawley rats were randomly divided into sham group (n=6) and operation group (n=19). The operation group was occluded the left middle cerebral arter-ies with modified Longa's methods for 90 minutes and reperfused, and twelve qualified rats of them were randomly divided into model group (n=6) and electroacupuncture group (n=6), the later accepted electroacupuncture at Baihui and Shenting for seven days. They were as-sessed with Longa's scores, and tested with Barnes maze. Their cerebral infarct volume was tested with magnetic resonance imaging T2-weighted image. The ultrastructure of synapse in hippocampal CA1 region was observed with transmission electron microscope. Results Compared with the model group, the Longa's score improved (P<0.05), the infarct volume decreased (P<0.01), the average escape latency decreased (P<0.01) and the times entering the wrong hole decreased (P<0.001) in the electroacupuncture group. Under the transmission elec-tron microscope, the number of synapse decreased in the model group, with the structure damage and vesicles sparse;compared with the model group, the number of synapse increased in the electroacupuncture group, with clear and complete structure and rich vesicles. Conclu-sion Electroacupuncture at Baihui and Shenting can improve the learning-memory function in rats after cerebral ischmeia-reperfusion, which may relate to improvement of synaptic plasticity and ameliorating ultrastructure in hippocampal CA1 region.
RESUMEN
Objective To investigate the relationship between learning and memory deficit and demyelination of the corpus callosum in twelve-month old APP/PS1 transgenic mice. Methods Twelve twelve-month old APP/PS1 transgenic mice were as AD group, and age-matched wild type (WT) littermates were as WT group. Learning and memory ability was tested with Morris water maze, and the mor-phology of nerve fiber of corpus callosum was detected with Luxol Fast Blue staining. Immunohistochemistry was used to detect myelin ba-sic protein (MBP) in the corpus callosum. Thioflavine S staining was used to detect amyloid plaque in the corpus callosum. Results Com-pared with WT group, the latency increased (Z>2.873, P<0.01) and the times crossing the location of the platform decreased (t=-7.339, P<0.001) in AD group. The nerve fibers were sparse and disorganized, with a lot of vacuoles in the corpus callosum of AD group. The positive expression of MBP in the corpus callosum was significantly decreased (t=-4.481, P<0.001) in AD group compared with WT group. There were amyloid plaques in the corpus callosum of AD group. Conclusion Twelve-month old APP/PS1 transgenic mice exhibit learning and memory deficit, which may be attributed to the deposition of the amyloid plaque mediated demyelinated injury of the corpus callosum.