The purpose of this study was to establish a method to record the dynamic process of vascular regeneration and remodeling in rat cerebral ischemic regions. An animal brain window model was established to continuously observe the changes of rat cortical vascular ischemia in vivo, and the model of cerebral ischemia was established by photochemical embolization. Optical coherence tomography (OCT) was performed to record the formation of vascular blockage and the injury and regeneration of small vessels during cerebral ischemia recovery. The results showed that 30 min of laser irradiation could completely block the cortical vessels in rats. Within 24-48 h after ischemia, the degree of brain injury was the greatest, and the number of blood vessels in the ischemic region reached the minimum. Then the blocked blood vessels began to be dredged, and the small blood vessels around the ischemic area began to regenerate. Small blood vessels in the superficial/deep layers of the cortex disappeared significantly after laser irradiation. During 10 d after ischemia, the blocked blood vessels were gradually dredged and recovered. On the 10th day after laser irradiation, a large number of neovascularization appeared in the superficial layer of cortex, but the deep vessels did not recover. These results indicate that the method established in this study can observe the changes of blood vessel in cerebral ischemic region continuously, which lays a foundation for further quantitative study on the dynamics of embolized blood vessels and peripheral capillaries during the recovery of cerebral ischemia.
Animals ; Brain ; blood supply ; Brain Ischemia ; Cerebral Cortex ; blood supply ; Rats ; Regeneration

OBJECTIVETo explore the correlations between the occurrence and severity of neglect and the region, range or extent of the decrease in regional cerebral blood flow (rCBF).

METHODSNineteen dextromanual patients who were diagnosed as unilateral stroke clinically and hemispatial neglect by a neglect test battery received single photon emission computed tomography (SPECT) scans.

RESULTSOn images, the damages of patients with neglect were seen most frequently in the frontal cortex, and then in turn in the parietal cortex, occipital cortex, temporal cortex, basal ganglia and thalamus. Most patients with neglect had two or more regions damaged. The most significant region was temporal-parietal-occipital (TPO) junction. The correlation coefficient between rCBF and the severity of neglect was -0.34 (t = -1.5, P > 0.05), and that between the decrease percentage of rCBF and the severity of neglect was 0.34 (t = 1.47, P > 0.05). The correlation coefficients between the range, number of foci, the flow deficit size and the severity of neglect were 0.71 (t = 4.13, P < 0.01), 0.70 (t = 4.07, P < 0.01) and 0.64 (t = 3.40, P < 1.01), respectively.

CONCLUSIONSThe severity of neglect correlates with rCBF and the decrease percentage of rCBF insignificantly, but correlates positively with the range, number of foci and the flow deficit size significantly. Hemispatial neglect is caused by the damage of multiple sites and combined damage results in more severe neglect.

Adult ; Aged ; Cerebral Cortex ; blood supply ; Female ; Frontal Lobe ; blood supply ; Humans ; Male ; Middle Aged ; Perceptual Disorders ; diagnostic imaging ; physiopathology ; Regional Blood Flow ; Tomography, Emission-Computed, Single-Photon

BACKGROUNDIn response to the inflammatory reaction, circulating leukocytes aggregate and adhere to the endothelial cells and eventually pervade into tissues, resulting in cell damage. This study was to detect the inflammatory reactions in mouse focal cerebral ischemia and their distinct characteristics in the ischemic basal ganglia and surrounding cortex.

METHODSMice were subjected to permanent occlusion of the left middle cerebral artery (MCAO) by introducing a suture for 2 to 120 hours. The expression of intercellular adhesion molecule 1 (ICAM-1) and Mac-1 was determined immunohistochemically. The myeloperoxidase (MPO) activity of the ischemic regions was measured.

RESULTSFour hours after MCAO, the number of ICAM-1 positive vessels in the ischemic basal ganglia increased (9.2 +/- 2.8 per mm(2)), peaked at 48 hours (29.6 +/- 4.8 per mm(2)), and decreased after 72 hours. In the ischemic cortex, the number increased rapidly 4 hours after MCAO (19.4 +/- 6.1 per mm(2)), peaked at 48 hours (44.4 +/- 16.8 per mm(2)), and declined after 72 hours. Mac-1 positive cells were seen in the ischemic basal ganglia (3.4 +/- 1.2 per mm(2)) 12 hours after MCAO, peaked after 48 hours (20.2 +/- 6.3 per mm(2)), and decreased after 72 hours. In the ischemic cortex, however, the number increased 4 hours after MCAO (4.3 +/- 1.7 per mm(2)), peaked after 48 hours (20.9 +/- 8.4 per mm(2)), and remained high at 120 hours. The MPO activity increased in the ischemic basal ganglia 12 hours after MCAO (0.111 +/- 0.023 U/g), peaked after 24 hours (0.194 +/- 0.059 U/g), and decreased after 72 hours. In the ischemic cortex, the MPO activity increased 12 hours after MCAO (0.110 +/- 0.032 U/g), peaked after 24 hours (0.210 +/- 0.067 U/g), and remained elevated at 120 hours.

CONCLUSIONSThe increased expression of ICAM-1 in the ischemic brain of mouse in the early phase of MCAO followed by the over-expression of Mac-1 and the increased MPO activity suggests that focal ischemia leads to early onset of inflammation. The inflammatory response is more persistent and intensive in the ischemic cortex than in the ischemic basal ganglia.

Animals ; Basal Ganglia ; blood supply ; Brain Chemistry ; Brain Ischemia ; metabolism ; pathology ; Cerebral Cortex ; blood supply ; Cerebrovascular Circulation ; Inflammation ; etiology ; Intercellular Adhesion Molecule-1 ; analysis ; Macrophage-1 Antigen ; analysis ; Male ; Mice ; Middle Cerebral Artery ; Peroxidase ; analysis

OBJECTIVETo develop a simple method for assessment of RNA integrity in laser capture microdissection (LCM) samples.

METHODSThe total RNA were isolated from the LCM samples and the sections before and after microdissection and examined by agarose gel electrophoresis. Real-time PCR was employed to assess the RNA from LCM samples, and the quantity of RNA was theoretically estimated according to the average total RNA product in mammalian cells (10 ng/1000 cells).

RESULTSWhen the total RNA from the sections before and after microdissection was intact, the RNA from LCM samples also had good quality, and the 28S and 18S rRNAs were visualized by ethidium bromide staining. Real-time PCR also showed good RNA quality in the LCM samples.

CONCLUSIONA simple method for quantitative and qualitative assessment of the RNA from LCM samples is established, which can also be applied to assessment of DNA or proteins in LCM samples.

Animals ; Capillaries ; pathology ; Cerebral Cortex ; blood supply ; pathology ; Lasers ; Male ; Microdissection ; methods ; Neurons ; pathology ; RNA ; analysis ; isolation & purification ; Rats ; Rats, Sprague-Dawley

The involvement of apoptosis in mitochondrial toxin 3-nitropropionic acid (3-NPA)-induced ischemic tolerance to transient focal cerebral ischemia in rats and the mechanism was investigated. 3-NPA at a dose of 20 mg/kg or vehicle control was intraperitoneally into the rats. Three days later, rats were exposed to 2 h of middle cerebral artery occlusion followed by 24 h of reperfusion. Infarct volumes were assessed by 2,3,5-triphenyltetrazolinm chloride (TTC) staining 24 h after reperfusion. Neural cell apoptosis in cerebral ischemic penumbra was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin in situ nick end labeling (TUNEL) and flow cytometry methods (FCM). The results showed that as compared to the vehicle-treated group, pretreatment with 3-NPA could reduce the infarct volume by 23.3% and decrease the number of TUNEL-positive neural cells and apoptotic percentage by 47% (P<0.05) and 44.9% (P<0.01), respectively. It was concluded that the development of 3-NPA-induced ischemic tolerance in brain might be related to the decreases in neural cell apoptosis.
Animals ; Apoptosis ; drug effects ; Cerebral Cortex ; blood supply ; Cerebrovascular Circulation ; DNA Damage ; Infarction, Middle Cerebral Artery ; pathology ; Ischemic Attack, Transient ; chemically induced ; pathology ; Ischemic Preconditioning ; Male ; Middle Cerebral Artery ; pathology ; Nitro Compounds ; Propionates ; Rats ; Reperfusion Injury ; pathology

OBJECTIVETo investigate morphological changes of capillary in aging brain and explore the role of vascular factor in brain aging.

METHODSTwenty-eight brains of individuals (mean age 65 years) who died without clinical or pathological involvement of nervous system and 6 brains of Alzheimer's disease (AD) patients (mean age 83 years) were obtained at autopsy. Sections from frontal lobe, occipital lobe, striatum and hippocampus of normal subjects and sections from hippocampus of AD patients were used for hematoxylin eosin (HE), lox fast blue (LFB), toluidine blue stains and ulex europaeus agglutinin (UEA) immunostaining. After observations of morphological changes of neuron and capillary, computer-aid image analysis was performed to quantify numerical density and area density of neuron and capillary in frontal lobe, occipital lobe, putamen, CA3 sector of normal subjects and CA3 sector of AD patients. Numerical ratio and area ratio of neuron and capillary were then calculated. Correlations between neuron/capillary ratio and age were estimated using Pearson's correlation test. Difference of neuron/capillary ratio in CA3 sectors between AD patients and advanced aged normal subjects (> 75 years) was analyzed with Student's t-test.

RESULTSSeveral pathological microvascular changes, including increased tortuosity, looping, bundling, stringing, and effacement of endothelia were seen in aged subjects and more prevalent in AD patients. Numerical ratio and area ratio of neuron and capillary of frontal lobe, occipital lobe and putamen significantly increased with age in normal aging subjects.

CONCLUSIONSMorphological changes and relative decrease in number and capacity of capillary in aging brain may reduce cerebral blood flow and metabolism, and consequently result in functional impairment of aging brain. Vascular factors may play an important role in the development of brain aging.

Adult ; Aged ; Aged, 80 and over ; Aging ; Alzheimer Disease ; etiology ; pathology ; Capillaries ; anatomy & histology ; pathology ; Cell Count ; Cerebral Cortex ; blood supply ; pathology ; Female ; Frontal Lobe ; blood supply ; pathology ; Hippocampus ; blood supply ; pathology ; Humans ; Image Processing, Computer-Assisted ; Male ; Middle Aged ; Neurons ; pathology ; Occipital Lobe ; blood supply ; pathology

Under global cerebral ischemia, the effect of different brain temperature on cerebral ischemic injury was studied. Male Sprague-Dawley rats were divided into normothermic (37-38°C) ischemia, mild hypothermic (31-32°C) ischemia, hyperthermic (41-42°C) ischemia and sham-operated groups. Global cerebral ischemia was established using the Pulsinelli four-vessel occlusion model and brain temperature was maintained at defined level for 60 min after 20-min ischemia. The expression of c-fos protein and the levels of malondialdehyde (MDA) and lactate in brain regions were detected by immunochemistry and spectrophotometrical methods, respectively. C-fos positive neurons were found in the hippocampus and cerebral cortex after cerebral ischemia reperfusion. Mild hypothermia increased the expression of c-fos protein in both areas, whereas hyperthermia decreased the expression of c-fos protein in the hippocampus at 24 h reperfusion, and the cerebral cortex at 48 h reperfusion when compared to normothermic conditions. In normothermic, mild hypothermic and hyperthermic ischemia groups, the levels of MDA and lactate in brain tissue were increased at 24, 48 and 72 h reperfusion following 20-min ischemia as compared with the sham-operated group (P<0.01). The levels of MDA and lactate in mild hypothermic group were significantly lower than those in normothermic group (P<0.01). It is suggested that brain temperature influences the translation of the immunoreactive protein product of c-fos after global cerebral ischemia, and MDA and lactate are also affected by hypothermia and hyperthermia.
Animals ; Body Temperature ; Brain ; blood supply ; metabolism ; physiopathology ; Brain Ischemia ; metabolism ; physiopathology ; Cerebral Cortex ; blood supply ; metabolism ; physiopathology ; Hippocampus ; blood supply ; metabolism ; physiopathology ; Immunochemistry ; Lactic Acid ; metabolism ; Male ; Malondialdehyde ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Proto-Oncogene Proteins c-fos ; metabolism ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; metabolism ; physiopathology ; Spectrophotometry ; Temperature ; Time Factors ; Tumor Suppressor Protein p53 ; metabolism

In this study, we tested the hypothesis that decreased cerebral perfusion pressure (CPP) induces cerebral ischemia and worsen brain damage in neonatal bacterial meningitis. Meningitis was induced by intracisternal injection of 10(9) colony forming units of Escherichia coli in 21 newborn piglets. Although CPP decreased significantly at 8 hr after bacterial inoculation, deduced hemoglobin (HbD), measured as an index of changes in cerebral blood flow by near infrared spectroscopy, did not decrease significantly. In correlation analyses, CPP showed significant positive correlation with brain ATP and inverse correlation with brain lactate levels. CPP also correlated positively with HbD and oxidized cytochrome aa3 (Cyt aa3) by near infrared spectroscopy. However, CPP did not show significant correlation with cerebral cortical cell membrane Na+,K+-ATPase activity, nor with levels of lipid peroxidation products. In summary, decreased CPP observed in this study failed to induce cerebral ischemia and further brain injury, indicating that cerebrovascular autoregulation is intact during the early phase of experimental neonatal bacterial meningitis.
Animal ; Animals, Newborn ; Blood Glucose/metabolism ; Cell Membrane/microbiology ; Cell Membrane/enzymology ; Cerebral Cortex/metabolism ; Cerebral Cortex/chemistry ; Cerebral Cortex/blood supply ; Cerebrovascular Circulation/physiology* ; Energy Metabolism/physiology* ; Escherichia coli Infections/physiopathology* ; Escherichia coli Infections/metabolism* ; Glucose/cerebrospinal fluid ; Glucose/analysis ; Intracranial Pressure ; Lactic Acid/cerebrospinal fluid ; Lactic Acid/blood ; Lactic Acid/analysis ; Lipid Peroxidation/physiology ; Meningitis, Bacterial/physiopathology* ; Meningitis, Bacterial/metabolism* ; Na(+)-K(+)-Exchanging ATPase/metabolism ; Spectroscopy, Near-Infrared ; Swine

OBJECTIVE: To determine the effects of naoyian (NYA) serum on the expression of vascular endothelial growth factor (VEGF) protein in cultured rat cerebral microvascular endothelial cell (RCMEC) with hypoxia. METHODS: NYA serum was separated from rat heart which had been filled stomach with NYA successively for 3 days. The rat cerebral microvascular endothelial cells were taken from the Sprageu-Dawley rat brain at postborn 7 days. The rat cerebral microvascular endothelial cells were incubated at anaerobic incubator to establish the hypoxia models. The vigo of RCMEC was determined by MTT. The level of expression of VEGF protein was measured by cell immunohistochemistry and Western blot. RESULTS: The OD value of NYA serum group was higher than the control groups after hypoxia for 18 hours. VEGF protein was increased by hypoxia in cerebral microvascular endothelial cells (P < 0.05). The content of VEGF protein in NYA serum containing medium was more significantly elevated than those cultured in other control media (P < 0.01). CONCLUSION VEGF protein was induced by hypoxia in rat cerebral microvascular endothelial cells, and NYA could upregulate the expression of VEGF protein, which may be one of the protection mechanisms for cerebral microvascular endothelial cells.
Animals ; Animals, Newborn ; Capillaries ; cytology ; Cell Hypoxia ; Cells, Cultured ; Cerebral Cortex ; blood supply ; Drugs, Chinese Herbal ; pharmacology ; Endothelium, Vascular ; cytology ; metabolism ; Female ; Male ; Rats ; Rats, Sprague-Dawley ; Serum ; Vascular Endothelial Growth Factor A ; biosynthesis ; genetics

BACKGROUNDRecent autopsy study showed a high incidence of cerebrovascular lesions in Alzheimer's disease (AD). To assess the impact of cerebrovascular pathology in AD, we used diffusion tensor imaging (DTI) to study AD patients with and without cerebrovascular lesions.

MATERIALS AND METHODSConventional and DTI scans were obtained from 10 patients with probable AD, 10 AD/V patients (probable AD with cerebrovascular lesions) and ten normal controls. Mean diffusivity (D) and fractional anisotropy (FA) values of some structures involved with AD pathology were measured.

RESULTSD value was higher in AD patients than in controls in hippocampus and the cingulate gyrus. In AD/V patients, increased D value was found in the same structures and also in the thalamus and basal ganglia compared to controls. There was a significant difference of D value between AD and AD/V patients. FA value reduced in the white matter of left inferior temporal gyrus and in the bilateral middle cingulate gyrus in patients with AD/V compared with controls. The MMSE (mini-mental state examination) score significantly correlated with FA value in the right hippocampus (r=0.639, P<0.019), in the right anterior cingulate gyrus (r=0.587, P<0.035) and in left parahippocampal gyrus (r=0.559, P<0.047).

CONCLUSIONCerebrovascular pathology had stronger impact on the D value than the AD pathology alone did. Elevated D value in thalamic and basal ganglia may contribute to cognitive decline in AD/V patients. Reduced FA values in AD/V patients may indicate that cerebrovascular pathology induced more severe white matter damage than the AD pathology alone did.

Aged ; Alzheimer Disease ; complications ; pathology ; Brain ; blood supply ; pathology ; Cerebral Cortex ; pathology ; Cerebrovascular Disorders ; complications ; pathology ; Cognition ; Corpus Callosum ; pathology ; Diffusion Magnetic Resonance Imaging ; Female ; Hippocampus ; pathology ; Humans ; Male ; Temporal Lobe ; pathology