ABSTRACT
Ischemic stroke is a leading cause of morbidity and mortality worldwide. Resident microglia are the principal immune cells of the brain, and the first to respond to the pathophysiological changes induced by ischemic stroke. Traditionally, it has been thought that microglial activation is deleterious in ischemic stroke, and therapies to suppress it have been intensively explored. However, increasing evidence suggests that microglial activation is also critical for neurogenesis, angiogenesis, and synaptic remodeling, thereby promoting functional recovery after cerebral ischemia. Here, we comprehensively review the dual role of microglia during the different phases of ischemic stroke, and the possible mechanisms controlling the post-ischemic activity of microglia. In addition, we discuss the dynamic interactions between microglia and other cells, such as neurons, astrocytes, oligodendrocytes, and endothelial cells within the brain parenchyma and the neurovascular unit.
ABSTRACT
<p><b>BACKGROUND</b>Connexin 43 (Cx43) is one of the major components of human keratinocyte gap junctions. To study whether gap junctional intercellular communication participates in the transfer of acupoint signals and acupuncture analgesia, the expression of Cx43 was studied in Zusanli (ST36) acupoints compared with control non-acupoint regions in rats after acupuncture. In addition, Cx43 heterozygous gene knockout mice were used to further explore the relationship between Cx43 and acupuncture analgesia.</p><p><b>METHODS</b>The expression of Cx43 was detected by immunohistochemistry, immunoblotting, and RT-PCR for the Cx43 protein and mRNA. The influence of the Cx43 gene knockout on acupuncture analgesia was measured by a hot plate and observing the writhing response on Cx43 heterozygous gene knockout mice.</p><p><b>RESULTS</b>Immunohistochemistry showed abundant Cx43 expression in some cells in the skin and subcutaneous tissue of rat ST36 acupoints. The mRNA and protein levels of Cx43 in acupoints were significantly higher than those in the control points in the non-acupuncture group, and even more so after acupuncture. The hot plate and writhing response experiments showed that partial knockout of the Cx43 gene decreased acupuncture analgesia.</p><p><b>CONCLUSION</b>Cx43 expression and acupuncture analgesia showed a positive correlation.</p>
Subject(s)
Animals , Female , Mice , Rats , Acupuncture Analgesia , Acupuncture Points , Blotting, Western , Connexin 43 , Genetics , Metabolism , Gene Expression Regulation , Genotype , Immunohistochemistry , Mice, Knockout , Pain , Metabolism , Pain Management , Random Allocation , Rats, Sprague-Dawley , Reverse Transcriptase Polymerase Chain ReactionABSTRACT
Objective To observe the effects of cell cycle inhibitor on astrocytic proliferation and scar formation and to study neuronal apoptosis after focal cerebral ischemia in rats.Methods Ischemic model was established by photochemistry method.T_2-weighted MRI was performed on the 3rd, 7th, and 30th day after focal cerebral ischemia.The expression of glial fibrillary acidic protein(GFAP)and apoptosis was observed by immunofluorescence.The protein levels of GFAP and proliferation cell nuclear antigen (PCNA), CyelinA and CyclinB1 were measured by Western blotting from the ischemic and sham animals finished on the 3rd, 7th, and 30th day.Results A marked and significant reduction of brain infarction volume was found in Olomoucine-treated ischemic animals(2.27%?0.28% , 1.87%?0.19%, 1.08%? 0.18%)as compared with controls(5.10%?0.35%, 4.60%?0.26%, 3.96%?0.28%, P