动物造模,脑缺血大鼠 z-bio 2022-10-18 295

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

　　Methods The rat model of focal cerebral ischemia was established by double ligation of the distal external carotid artery for 60 minutes. The preparation of the model was evaluated by the neurological deficit score. The successful rats were divided into model group, electroacupuncture group and nimodipine group, and the sham operation group was treated as control. After 3 weeks of treatment, the neurological deficit score was used to evaluate the degree of brain damage of rats in each group; The cerebral infarction volume of rats in each group was measured by 2,3,5-triphenyltetrazolium chloride (TTC) staining; The synaptic ultrastructure of cerebral cortex was observed by electron microscope and analyzed by morphometry; Immunofluorescence staining was used to observe the polarization of microglia in cerebral cortex; The level of miR-21 in cerebral cortex of rats in each group was measured by qRT-PCR; 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 measured by Western blot.

　　Results Compared with the sham operation group, the neurological deficit score, infarct volume, the number of M1 microglia in cerebral cortex, the levels of miR-21, p-STAT3, p-JAK2, the number of M2 microglia in cerebral cortex, the number density of synaptic surface (Nv), the density of synaptic body (Vv), the density of synaptic junction zone (Sv), the density of post synaptic dense substance (PSD), the surface ratio of synaptic interface The width of synaptic space decreased significantly (P<0.05); Compared with the model group, the scores of neurological impairment, cerebral infarct volume, the number of M1 microglia, miR-21, p-STAT3, p-JAK2 levels in the electroacupuncture group and nimodipine group were significantly decreased (P<0.05), while the number of M2 microglia, Nv, Vv, Sv, PSD, the rate of synaptic interface curvature, and the width of synaptic gap were significantly increased (P<0.05).

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