动物造模 z-bio 2022-10-10 513

　　Objective To investigate synaptic plasticity and microglial polarization in rats with focal cerebral ischemia by electroacupuncture, and to detect the expression of miR-21/signal transducer and activator of transcription 3 (STAT3) pathway.

　　Methods A focal cerebral ischemia rat model was established by double ligation of the distal end of the external carotid artery with a thin thread for 60 min. The neurological deficit score was used to evaluate the preparation of the model. The successful model rats were divided into a model group, an electroacupuncture group and a nimodipine group. , while the sham-operated group was treated as a control. After 3 weeks of treatment, the neurological deficit score was used to evaluate the degree of brain injury in each group; 2, 3, 5-triphenyltetrazolium chloride (TTC) staining was used to determine the volume of cerebral infarction in each group; electron microscopy was used to observe the cerebral cortical process Ultrastructure and morphometric analysis; immunofluorescence staining to observe the polarization of cerebral cortical microglia; quantitative real-time PCR (qRT-PCR) method to determine the level of miR-21 in the cerebral cortex of rats in each group; Western blotting method The levels of Janus protein tyrosine kinase 2 (JAK2), p-JAK2, STAT3 and p-STAT3 in the cerebral cortex of rats in each group were determined.

　　Results Compared with the sham operation group, the neurological deficit score, the infarct volume, the number of M1-type microglia in the cerebral cortex, and the levels of miR-21, p-STAT3 and p-JAK2 in the model group were significantly increased (P<0 . 05), the number of M2-type microglia in the cerebral cortex, the number density of synapses (Nv), the density of synaptosomes (Vv), the density of synaptic junctions (Sv), the density of postsynaptic densities (PSD) , synaptic interface surface rate and synaptic cleft width were significantly decreased (P<0.05); compared with the model group, the neurological deficit score, cerebral infarction volume, M1-type microgum in the electroacupuncture group and nimodipine group were significantly reduced (P<0.05). The number of cytoplasmic cells, miR-21, p-STAT3, p-JAK2 levels were significantly decreased (P<0.05), the number of M2-type microglia, Nv, Vv, Sv, PSD, synaptic interface surface rate, synaptic Gap width was significantly increased (P<0.05).

　　Conclusion Electroacupuncture can promote synaptic reconstruction in rats with focal cerebral ischemia and induce the polarization of microglia from M1 to M2 type.