Expression of vimentin and glial fibrillary acidic protein in central nervous system development of rats

Objective To investigate the distribution and contents of vimentin (Vim) and glial fibrillary acidic protein (GFAP) immunoreactivities in the central nervous system (CNS) of normal newborn, adult and aged rats. Methods In this study, thirty healthy and normal Sprague–Dawley rats were simply classified into three groups: Newborn (7 days aged), adult (5 months aged) and aged (24 months aged) rats. Brains and spinal cord were dissected and cut into frozen sections. The expression of Vim and GFAP in CNS were detected by confocal immunofluorescence. Results In each group, Vim was expressed in all the regions of CNS including the hippocampal, cerebral cortex, the third ventricle and spinal cord, and the expression was highest in neuron-like cell of newborn rats, while Vim was mainly expressed in cell bodies in adult and aged rats. GFAP was expressed in all the regions of CNS including the hippocampal, cerebral cortex, the third ventricle and spinal cord, and the expression was in astrocytes of aged rats. In the third ventricle, Vim was detected in all groups, and only observed in neuron-like cells of newborn. Meanwhile, the GFAP expression showed no significant differences between adult and aged rats in this region. The co-localization of Vim and GFAP were mainly observed in hippocampus and cerebral cortex of newborn, but this co-localization was found in the third ventricle of the rats in all groups. Conclusion Our data demonstrate for the first time that the expression of Vim and GFAP in the rat's CNS during development. This data may provide a foundation for the further mechanistic studies of these two main intermediate filaments during development of CNS.

Expression of vimentin and glial fibrillary acidic protein in central nervous system development of rats

OBJECTIVE@#To investigate the distribution and contents of vimentin (Vim) and glial fibrillary acidic protein (GFAP) immunoreactivities in the central nervous system (CNS) of normal newborn, adult and aged rats.@*METHODS@#In this study, thirty healthy and normal Sprague-Dawley rats were simply classified into three groups: Newborn (7 days aged), adult (5 months aged) and aged (24 months aged) rats. Brains and spinal cord were dissected and cut into frozen sections. The expression of Vim and GFAP in CNS were detected by confocal immunofluorescence.@*RESULTS@#In each group, Vim was expressed in all the regions of CNS including the hippocampal, cerebral cortex, the third ventricle and spinal cord, and the expression was highest in neuron-like cell of newborn rats, while Vim was mainly expressed in cell bodies in adult and aged rats. GFAP was expressed in all the regions of CNS including the hippocampal, cerebral cortex, the third ventricle and spinal cord, and the expression was in astrocytes of aged rats. In the third ventricle, Vim was detected in all groups, and only observed in neuron-like cells of newborn. Meanwhile, the GFAP expression showed no significant differences between adult and aged rats in this region. The co-localization of Vim and GFAP were mainly observed in hippocampus and cerebral cortex of newborn, but this co-localization was found in the third ventricle of the rats in all groups.@*CONCLUSION@#Our data demonstrate for the first time that the expression of Vim and GFAP in the rat's CNS during development. This data may provide a foundation for the further mechanistic studies of these two main intermediate filaments during development of CNS.

Effect of precursor of brain-derived neurotrophic factor on hippocampal neuron survival and its mechanism / 中南大学学报(医学版)

OBJECTIVE@#To explore the effect of precursor of brain-derived neurotrophic factor (proBDNF) on cultured hippocampal neuron and its intracellular mechanism.@*METHODS@#The hippocampal neurons were dissociated from E18 rats and cultured in neurobasal medium, and then the cells were treated with proBDNF, preBDNF(propeptide of proBDNF) and proBDNF antiserum,respectively. Thirty minutes, 1 hour or 48 hours later, the cells were stained with Nissl solution, and the immunocytochemistry methods of ELK-p (Ets domain protein), ErK2(extracellular signal regulated kinase) and c-fos were performed.@*RESULTS@#The expressions of ELK-p, ErK and c-fos were significantly upregulated in the cultured hippocampal neurons after they were treated with proBDNF protein,and the immuno-positive staining was also obvious in some nuclei. While the endogenous proBDNF was neutralized by proBDNF antiserum treatment, the expressions of ELK-p, ErK and c-fos were downregulated and many cells showed swelling and vasoculation. The immunoreactivity in preBDNF treated cells was similar to that in normal cultured cells.@*CONCLUSION@#proBDNF plays an important role in sustaining the hippocampal neuron survival through upregulating the ELK and ErK pathways.

Expression of eNOS in the endothelial cells during the arteriogenesis of pig hind-limbs / 中南大学学报(医学版)

OBJECTIVE@#To detect the expression and activity of eNOS during the arteriogenesis of hind-limbs of pigs.@*METHODS@#The right femoral artery was ligated, and the left femoral artery shamly operated under routine surgical procedures. Animals were sacrificed after two weeks. The expression and activity of eNOS in collateral vessels were studied by confocal immunofluorescence with antibodies against eNOS and phosphorylated eNOS (P-eNOS) respectively.@*RESULTS@#In normal small arteries, the expression of eNOS was very low, and the staining was very weak. In growing collateral vessels, the expression of eNOS was significantly up-regulated, showing very strong positive staining. The expression of P-eNOS was also high. Dural immunostaining showed that eNOS and P-eNOS were colocalized in the endothelial cells.@*CONCLUSION@#eNOS is up-regulated and activated during arteriogenesis, suggesting that eNOS can exert the possible role in mediating the proliferation of endothelial cells and the inflammation, and contribute to the collateral vessel growth.

Effect of polygonum multiflorum thunb on BDNF expression in rat hippocampus induced by amyloid beta-protein (Abeta) 1-40 / 中南大学学报(医学版)

OBJECTIVE@#To explore the effect of polygonum multiflorum thunb (PMT) on the expression of brain-drived neurtrophic factor (BDNF) in hippocampus CA1 in rats induced by Abeta1-40.@*METHODS@#The rat model was established by injecting Abeta1-40 into the right dorsal hippocampus in rats, and their behavior was observed by Y-maze. The morphological changes of rat hippocampus were examined by the Nissl staining. The expression of BDNF in hippocampus CA1 neurons was also examined by immunohistochemistry and Western blot.@*RESULTS@#After the administration of Abeta1-40, the times of rats learning how to elude electric stimulation were significantly increased, and the expression of BDNF in hippocampus CA1 were obviously reduced. The aggregation of Abeta1-40 in hippocampus and the morphological changes of CA1 hippocampus were found. After the treatment with PMT for 30 days, the times learning how to elude electric stimulation were obviously reduced, while the expression of BDNF in hippocampus CA1 was also increased.@*CONCLUSION@#PMT can reverse the down-regulation of BDNF expression in hippocampus CA1 induced by Abeta1-40.

Pathway for macrophage invasion into the tunica media and the intima in vein graft / 中南大学学报(医学版)

OBJECTIVE@#To test whether the macrophages in vein grafts may invade into the vascular wall from the adventitia apart from the lumen.@*METHODS@#Expression of CD68 (a marker of macrophage) and CD31 (a marker of endothelial cells) in 30 vein grafts were detected by confocal immunofluroscence. Images were processed with Silicon Graphics Octane.@*RESULTS@#In normal veins, there were a few CD68 positive cells in the adventitia, but few CD68 positive cells were found in the media and the intima. In the diseased vein, CD68 positive cells were significantly increased and present in all layers of the vascular wall, the adventitia, media and intima, extending from the adventitia to the media. There was a close relationship between the penetration of CD68 positive cells into the media from the adventitia and the angiogenesis in the media.@*CONCLUSION@#The adventitia may be an important pathway for macrophage invasion.