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Objective: To investigate the possible role of astrocytes after brain infarction in stroke-prone, spontaneously hypertensive (SHR-SP) rats and the association with angiogenesis and the architecture. Methods: We maintained SHR-SP rats on high sodium water starting to accelerate the stroke onset. The 3D quantification of microvasculatures (diameter, branch number) by cofocal microscope after FITC-dextran was injected into the rats via the left femoral vein. Glial fibrillary acidic protein (GFAP) expression and microvessel density (MVD) using counting the number of factor -positive endothelial cells were evaluated by immunofluorescence and immunohistochemistry, respectively. Results: Cerebral infarction occurred at week 7 after high sodium water intake (13 g/L NaCl) in SHR-SP group. When compared with the non-infarcted contralateral hemisphere and SHR-SP on normal sodium intake and WKY rats, GFAP expression and MVD were significantly increased, respectively, and the diameter and the branch number of vessels were decreased, respectively, in cerebral infarcts with boundary zones of SHR-SP rats (P<0.01). Linear correlation analysis showed that GFAP expression was positively correlated with MVD and the diameter and the branch number of vessels in cerebral infarcts in SHR-SP (P<0.01). Conclusion: Astrocytes hyperplasia may be associated with increased regional angiogenesis and the changes of architecture in SHR-SP rats with high sodium water (13 g/L NaCl) that induces focal cerebral infarcts.
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Objective To investigate the damage of hippocampal neurons induced by chronic cerebral ischemia in the rats,and to clarify its mechanism.Methods 90 healthy adult male SD rats were randomly divided into sham operation group (n=30 ) and experimental group (n=60 ). The chronic cerebral ischemia rat models were established by permanently ligating the common carotid arteries on both sides of the rats in experimental group.The rats in sham operation group were established by incising the cervical median,only the common carotid arteries on both sides were separated without ligating. The rats in sham operation group and experimental group were respectively sacrificed at the 7th,14th and 21st day after operation.At each time point 10 rats in sham operation group and 20 rats in experimental group were selected and sacrificed.Immunohistochemistry staining was used to observe the dynamic changes of the expression levels of choline acetyltransferase(ChAT)in hippocampus neurons, and TA-FE method was used to observe the dynamic changes of hippocampal microvascualr architecture. MiVnt image analytical system was used to quantitatively analyze the immunohistochemistry result,the microvessel density (MVD)and micorvessel area density (MVA)of horizontal part of hippocampus in the rats. Results Compared with sham operation group,the ChAT expression levels in hippocampus neurons of the rats in experimental group at different time points were significantly decreased(P<0.05);and with the prolongation of time,the ChAT expression levels were gradually decreased;the ChAT expression level in 14-day experimental group was significantly lower than that in 7-day experimental group (P<0.05 );the ChAT expression level in 21-day experimental group was significantly lower than those in 7-day and 14-day experimental groups(P<0.05).The MVD and MVA of hippocampus of the rats in experimental group at different time points were obviously decreased compared with sham operation group(P<0.05);the MVA was gradually decreased with the prolongation of time, and the MVA of hippocampus of the rats in 21-day and 14-day experimental groups were obviously decreased compared with 7-day experimental group(P<0.05);the MVD was gradually decreased with the prolongation of time,the MVD of hippocampus of the rats in 21-day and 14-day experimental groups was obviously decreased compared with 7-day experimental group(P<0.05);the MVD of hippocampus of the rats in 21-day experimental group was obviously decreased compared with 14-day experimental group(P<0.05).Conclusion Chronic cerebral ischemia can lead to the progressive decrease of the ChAT expression level,MVD and MVA of hippocampus of the rats to aggravate gradually the learning and memory dysfunction, which may be one of the reasons of vascular dementia.
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Objective To observe three-dimensional(3-D) morphological features of microvessel architecture of human anaplastic astrocytoma.Methods Serial sections of human anaplastic astrocytoma were used to label microvascular endothelial cells with immunohistochemistry using anti-human FⅧ-RAg antibody.The serial images were taken and processed with computer-assisted 3-D reconstruction.Results Partial 3-D structures of the microvessels in anaplastic astrocytoma were successfully reconstructed.The morphology of the vessels was strange in their distribution and branching,which were completely different from normal microvessels of the brain.Some of the tumor vessels showed chaotic structure and some showed tubiform caecum.Conclusion Microvessels in anaplastic astrocytoma appeared multiformity and heterogeneity as well as abundance.3-D reconstruction of such features might be of significance in identifying their architecture,constructing digital tumor microvessel models and targeting the vessels in anti-angiogenesis therapy.
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The microvascular systematic architecture of the cerebral cortex were studied in six rabbits. The internal carotids were injected with Chinese ink via a cannula. After fixation, brains were removed and made sections of 80-220?m thick. Some sections were counterstained with HE or Nissl method in order to observe the histological structure of the microvessels and the relationship between the vessels and the nervous tissue.Morphometric measurements of the microvessels were made according to the Strahler system. Results were as follows.(1) In the cerebral cortex, the microarteries and microvenes could be subdivided in to four orders. (capillaries were considered as O order), Perforating branches were perpendicular to the surface of the cerebral cortex and the distribution area of a microartery trunk was in a columnar shape with a radius of 204.5 ?m. This was in compliance with the size of a functional column of the cerebral cortex.(2) For microarteries from order 1 to 4, the branching ratio was 3.72, the diameter ratio was 1.42, the segmental length ratio was 1.82; while for microvenes from order 1 to 4, the branching ratio was 3.25, the diameter ratio was 1.73, and the segmental length ratio was 2.25.(3) The total length of the true capillary network per unit volume of the cerebral cortex was 5.82?10~5?m/mm~3. The density of the capillary network of the cerebral cortex was highest in fourth and fifth layers, while the first layer was rather scarce in capillary network. The number of neurons within each lattice of the capillary network was most numerous in the fourth layer, 4.36 per lattice.According to the results mentioned above, the functional significance of the microvascular architecture and the microcirculation dynamics of the brain was also discussed.
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The micro-vascular architecture of the mucosa and submucosa of human tongue was studied under the surgical microscope and scanning electron microscope. The long branches of the profunda lingual arteries and the terminal branches of the dorsal lingual arteries anastomose into a thick layer of arterial network, under the mucosa and over the superficial muscle of the whole body and root of the tongue. Arteriolae spring from the submucosal arterial network, which get into the mucosa to form the capillary network of mucosa and the 9apillary plexuses of variant papillae.The relationship between the architecture of the lingual submucosal arterial network and the design of flaps, and the clinical significance of tongue diagnostic signs has been discussed.
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Objective To study the architecture of the subpleural pulmonary microvasculature and its functional relationship in the bactrian camel. Methods The replica scanning electron microscopic method was used. Results According to their continuous branches,the subpleural pulmonary microvasculatures were recognized into four grades: arteriole,terminal arteriole,precapillary arteriole and capillary.The subpleural pulmonary capillaries generally came from the subpleural precapillary arteriole and communicated each other to form the subpleural pulmonary capillary network.Sometimes,the subpleural terminal arteriole directly gave rise to capillaries to unite with the subpleural pulmonary capillary network.The network was loose,in which the diameter of the mesh was larger than that of the capillary,and the mesh was often hexagon and pentagon in appearance.There were obvious imprints of the smooth muscles on the surface of the casts of the subpleural pulmonary arteriole,the terminal arteriole and the precapillary arteriole.On the surface of the casts of the subpleural pulmonary capillary,there were obvious imprints of the endothelial nuclei as well.In addition,the broad and different level communications were found among the pulmonary interstitial capillary and subpleural pulmonary microvasculature.Conclusion There were no significant differences on the architecture of the subpleural pulmonary microvasculature between the bactrian camel and other kind of mammals.
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The origin, diameter, arrangement pattern, distribution and microvascular architecture of the intracerebral segments(IS) of the central branches of the middle cerebral artery(MCA) were examined and pictured in 27(10 infants, 5 newborns, 12 fetuses) unfixed brains under stereoscopic microscope and scanning electron microscope. 1. The extracerebral segments(ES) of the central branches run toward the anterior perforated substance in S-shaped curves. The IS arise from ES or their collateral branches. They form the fan-shaped appearance in rostromedial and caudolateral state after entering brain. 2. The IS give rise collateral branches in right or acute angles, and they are of two kinds: the longitudinal and the transverse branches. The mean diameter of the IS in original site is 0.21?0.18mm for the medial group; 0.36?1 0.21mm for the lateral group. 3. The medial group mainly distribute in the rostal part of the internal capsule and basal nucleus; the lateral group mainly distribute in the caudal part. 4. Some circular impressions of the precaillary sphincters were observed at the beginning of precapillary arteriole and capillary, converging point of tributary branches of venule. The relationship between the IS of the central branches and the hemodynamics was discussed.