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1.
Orexin A (ORX-A) is implicated in the regulation of various physiological processes, including sleep/wake cycles and reward/motivation. The hypothalamic ORX-A neurons project throughout the brain and spinal cord. In the present study we established and compared ORX-A levels in lumbar and ventricular cerebrospinal fluid (CSF) samples, drawn from idiopathic normal pressure hydrocephalus (INPH) patients, during respectively, lumbar puncture and shunt placement. Ventricular and lumbar CSF levels of total protein and of the dopamine, serotonin and norepinephrine metabolites HVA, 5-HIAA and MHPG respectively, were also estimated. ORX-A was quantified using a commercially available radioimmunoassay kit. Neurotransmitter metabolites were quantified by high performance liquid chromatography. Expectedly, HVA and 5-HIAA levels were significantly higher and total protein levels lower in ventricular compared to lumbar CSF while there were no differences in MHPG levels. However, in contrast to HVA and 5-HIAA and similar to total protein, lumbar ORX-A levels were significantly higher than ventricular levels. The higher lumbar compared to ventricular ORX-A levels may reflect elevated contributions from the spinal cord. The finding of a ventriculo-lumbar difference for ORX-A should be considered in studies utilizing its CSF levels in assessing Orexin system status.  相似文献   

2.
3,4-Dihydroxyphenylethylamine (DA, dopamine) and 5-hydroxytryptamine (5-HT) turnover values were determined in freely moving male rats by measuring the rates of accumulation of the acidic metabolites of the above transmitters, i.e., 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), and 5-hydroxyindoleacetic acid (5-HIAA) in cisternal cerebrospinal fluid (CSF) samples after probenecid (200 mg/kg i.p.) administration. Determinations on samples before and after acid hydrolysis showed that the latter procedure was necessary for DA turnover determination. Thus whereas total (DOPAC + HVA) increased linearly with time after probenecid, free (DOPAC + HVA) did not. This was because the percentage of DOPAC + HVA in conjugated form increased with time. Determinations on a group of 28 rats during the dark (red light) period showed that cisternal amine metabolite concentrations before probenecid injection did not parallel turnover values. This was probably because individual differences in metabolite egress strongly affect the pre-probenecid values. The poor correlations between CSF tryptophan and 5-HT turnover suggested that differences of brain tryptophan concentration were not major determinants of differences of brain 5-HT metabolism within this group of normal rats. Considering that the rats were of similar weight and that the turnover values were all determined at approximately the same time of day, the three- to fourfold ranges of the turnover values are remarkable. The positive correlation between the DA and 5-HT turnovers of individual rats suggests the existence of common effects on DA and 5-HT turnover in normal rats.  相似文献   

3.
IntroductionHIV-1 RNA can be found at higher levels in cerebrospinal fluid (CSF) than in plasma, termed CSF/plasma discordance. The clinical significance of CSF/plasma discordance is not known and the degree of discordance considered important varies. We aimed to determine whether a panel of CSF cytokines, chemokines and associated mediators were raised in patients with CSF/plasma discordance at different levels.MethodsA nested case-control study of 40 CSF samples from the PARTITION study. We used a cytometric bead array to measure CSF mediator concentrations in 19 discordant and 21 non-discordant samples matched for plasma HIV-1 RNA. Discordant samples were subdivided into ‘high discordance’ (>1log10) and ‘low discordance’ (0.5–1log10, or ultrasensitive discordance). CSF mediators significant in univariate analysis went forward to two-way unsupervised hierarchical clustering based on the patterns of relative mediator concentrations.ResultsIn univariate analysis 19 of 21 CSF mediators were significantly higher in discordant than non-discordant samples. There were no significant differences between samples with high versus low discordance. The samples grouped into two clusters which corresponded to CSF/plasma discordance (p < 0.0001). In cluster one all mediators had relatively high abundance; this included 18 discordant samples and three non-discordant samples. In cluster two all mediators had relatively low abundance; this included 18 non-discordant samples and one non-discordant sample with ultrasensitive discordance only.ConclusionsCSF/plasma discordance is associated with potentially damaging neuroinflammatory process. Patients with discordance at lower levels (ie. 0.5–1log10) should also be investigated as mediator profiles were similar to those with discordance >1log10. Sensitive testing may have a role to determine whether ultrasensitive discordance is present in those with low level CSF escape.  相似文献   

4.
Objective The diagnosis of multiple sclerosis (MS) is still challenging recently due to the lack of a specific diagnostic test. Proteomics analysis was applied to biomarkers discovery and their pathways study. Methods First, the proteins of CSF from MS patients and control group were analyzed individually with 2D-DIGE technology (two-dimensional difference gel electrophoresis). Then, protein spots were found out with DeCyder6.0 software which showed different expression levels in the gel images between the two groups. The information regarding these proteins was collected based on MALDI-TOF/MS and related database searches. Lastly, interaction between these proteins was further analyzed by using Metacore software. Results There were 13 proteins that showed more than 1.5-fold difference in expression levels between the two groups. Furthermore, the identification made by MALDI-TOF/MS revealed that one of the most significant differential proteins was DBP (vitamin D-binding protein), which decreased in the experimental group. This result was confirmed by ELISA (< 0.01). Moreover, network between the 13 proteins were partially got, which showed some biological interactions. Conclusion These results support a correlation between the level of DBP and MS. DBP may be a potential useful biomarker for diagnosis or a medicine target for treatment of MS.  相似文献   

5.
The concentration of free myo-inositol in CSF was determined with a gas chromatographic-mass spectrometric method using deuterated myo-inositol as an internal standard after conversion to the hexa-O-acetyl derivative with acetic anhydride and pyridine. Twenty microliters of CSF is sufficient for the analysis which has a coefficient of variation of 9%. Identical analytical results were obtained on two different mass numbers. Schizophrenic patients were compared with healthy control persons. In addition, patients with rheumatoid arthritis or with neurological illnesses were studied. No consistent differences related to the illness could be found. The mean concentration of myo-inositol was about 25 micrograms/ml. Treatment of schizophrenic patients with chlorpromazine or sulpiride had no significant effect on the concentration of myo-inositol in CSF.  相似文献   

6.
Abstract: Neural cell adhesion molecule (N-CAM) is involved in cell-cell interactions during synaptogenesis, morphogenesis, and plasticity of the nervous system. Disturbances in synaptic restructuring and neural plasticity may be related to the pathogenesis of several neuropsychiatric diseases, including mood disorders and schizophrenia. Disturbances in brain cellular function may alter concentrations of N-CAM in the CSF. Soluble human N-CAM proteins are detectable in the CSF but are minor constituents of serum. We have recently found an increase in N-CAM content in the CSF of patients with schizophrenia. Although the pathogenesis of both schizophrenia and mood disorders is unknown, ventriculomegaly, decreased temporal lobe volume, and subcortical structural abnormalities have been reported for both disorders. We have therefore measured N-CAM concentrations in the CSF of patients with mood disorder. There were significant increases in amounts of N-CAM immunoreactive proteins, primarily the 120-kDa band, in the CSF of psychiatric inpatients with bipolar mood disorder type I and recurrent unipolar major depression. There were no differences in bipolar mood disorder type II patients as compared with normals. There were no significant effects of medication treatment on N-CAM concentrations. It is possible that the 120-kDa N-CAM band present in the CSF is derived from CNS cells as a secreted soluble N-CAM isoform. Our results suggest the possibility of latent state-related disturbances in N-CAM cellular function, i.e., residue from a previous episode, or abnormal N-CAM turnover in the CNS of patients with mood disorder.  相似文献   

7.
We examined the effect of respiratory acidosis on the Na-HCO3 cotransporter activity in primary cultures of the proximal tubule of the rabbit exposed to 10% CO2 for 5 min, 2, 4, 24 and 48 hr. Cells exposed to 10% CO2 showed a significant increase in Na-HCO3 cotransporter activity (expressed as % of control levels, 5 min: 142 ± 6, 2 hr: 144 ± 13, 4 hr: 145 ± 11, 24 hr: 150 ± 15, 48 hr: 162 ± 24). The increase in activity was reversible after 48 hr. The role of protein kinase C (PKC) on the stimulatory effect of respiratory acidosis on the cotransporter was examined in presence of PKC inhibitor calphostin C or in presence of PKC depletion. Both calphostin C and PKC depletion prevented the effect of 10% CO2 for 5 min or 4 hr to increase the activity of the cotransporter. 10% CO2 for 5 min or 4 hr increased total and particulate fraction PKC activity. To examine the role of phosphotyrosine kinase (PTK) on the increase in cotransporter activity we studied the effect of two different inhibitors, 2-hydroxy-5-(2,5-dihydroxylbenzyl) aminobenzoic acid (HAC) and methyl 2,5-dihydroxycinnamate (DHC) which inhibit phosphotyrosine kinase in basolateral membranes. Cells were pretreated either with vehicle or HAC or DHC and then exposed to 10% CO2 for 5 min or 4 hr. In cells treated with vehicle, 10% CO2 significantly increased cotransporter activity as compared to control cells exposed to 5% CO2. This stimulation by 10% CO2 was completely prevented by HAC or DHC at 5 min (5% CO2: 1.8 ± 0.2, 10% CO2: 2.6 ± 0.2, 10% CO2+ HAC: 1.6 ± 0.2, 10% CO2: +DHC: 2.0 ± 0.3 pH unit/min) and also at 4 hr. The protein synthesis inhibitors actinomycin D and cycloheximide appear to prevent the effect of 10% CO2 for 4 hr on the cotransporter. Our results show that early respiratory acidosis stimulates the Na-HCO3 cotransporter through PKC and PTK-dependent mechanisms and the late effect appears to be mediated through protein synthesis. Received: 28 March 1997/Revised: 22 December 1997  相似文献   

8.
Patients with normal pressure hydrocephalus who had three lumbar punctures during 1 week ingested either water, a protein breakfast, or a carbohydrate breakfast 2.5 h before each of the lumbar punctures. The CSF was analyzed for biogenic amine precursors and metabolites. The protein meal raised CSF tyrosine levels, a finding consistent with animal data, but did not alter those of tryptophan or any of the biogenic amine metabolites. The carbohydrate meal increased CSF 3-methoxy-4-hydroxyphenylethylene glycol, an unexplained finding. The carbohydrate meal did not affect CSF tryptophan, tyrosine, 5-hydroxyindoleacetic acid, or homovanillic acid. Our results support the idea that in humans protein or carbohydrate meals do not alter plasma amino acid levels sufficiently to cause appreciable changes in CNS tryptophan levels or 5-hydroxytryptamine synthesis.  相似文献   

9.
Clusterin is suggested to be involved in the pathogenesis of Alzheimer's disease. Clusterin expression is increased in brain tissue in affected regions of Alzheimer patients, and intense clusterin staining is found in both senile plaques and in neuronal and glia cells. In contrast, the cerebrospinal fluid level of clusterin in Alzheimer patients has, thus far, been found unchanged. Clusterin is a glycosylated protein, and an alteration of its glycosylation in Alzheimer's disease might influence accurate quantification in cerebrospinal fluid through interference of antibody binding to the protein. Using enzymatic deglycosylation of clusterin isolated from cerebrospinal fluid, we found that the carbohydrates attached to clusterin were of the N-linked type and sialic acids. Based on this finding, cerebrospinal fluid samples from Alzheimer patients (n = 99) and controls (n = 39) were analysed. The samples were treated with peptide: N-glycanase F, cleaving off N-linked carbohydrates, and clusterin was quantified before and after deglycosylation using a new sandwich enzyme-linked immunosorbent assay. Clusterin was significantly increased in Alzheimer patients, in both native (7.17 ± 2.43 AU versus 5.73 ± 2.09 AU; p = 0.002), and deglycosylated samples (12.19 ± 5.00 AU versus 9.68 ± 4.38 AU; p = 0.004). Deglycosylation led to increased measured levels of clusterin by 70% (p < 0.001) in Alzheimer patients and 67% (p < 0.001) in controls. These findings indicate that glycosylation of proteins may interfere with their quantification. The results show that clusterin is significantly increased in cerebrospinal fluid from Alzheimer patients as a group, supporting that clusterin might be involved in the pathogenesis of Alzheimer's disease. However, the individual clusterin levels overlap between the two groups, and thus cerebrospinal fluid clusterin measurement is not suitable as a biochemical marker in the diagnosis of Alzheimer's disease.  相似文献   

10.
3-Nitrotyrosine is a useful marker for nitric oxide-mediated tissue injury. However, which proteins are preferred peroxynitrite modification targets is unclear. Chondroitin sulfate proteoglycans (CSPGs) abnormally accumulate in cerebrospinal fluid of human neonates with hydrocephalus and may be a target for peroxynitrite modification. We examined (1). whether CSPG core protein can be modified by peroxynitrite in vitro; (2). to what degree in comparison to bovine serum albumin (BSA), the most commonly used nitrated protein standard; (3). whether nitrated CSPGs can be measured directly in biological samples; and (4). whether nitrated proteoglycan concentrations in cerebrospinal fluid correlate with disease. In vitro nitration of bovine aggrecan was performed by exposure to different peroxynitrite concentrations, and 3-nitrotyrosine products were measured. Bovine serum albumin (BSA) nitration was also performed in comparison. A larger percentage of tyrosine residues were nitrated in aggrecan than in BSA under all conditions tested. An enzyme-linked immunosorbent assay (ELISA) for 3-nitrotyrosine consistently overestimated aggrecan nitration when nitrated BSA was used as the standard. This is important as most current assays of nitration in biological samples use nitrated BSA as the standard. Therefore, if nitrated CPSGs were a substantial portion of the nitrated proteins in a sample, total nitrated protein content would be overestimated. Aggrecan retained its function of binding hyaluronic acid despite substantial nitration. A double-sandwich ELISA was developed for nitrated CSPGs in biological samples, using nitrated aggrecan as standard. [Nitrated CSPG] was found to be significantly elevated in preterm hydrocephalus cerebrospinal fluid (P<0.02), but correlated poorly with cerebrospinal fluid [nitric oxide] (P>0.069), suggesting that nitrated CSPG and NO levels may be independant markers of tissue injury. Peroxynitrite-mediated protein tyrosine nitration is a previously unrecognized modification of CSPGs, and may reflect level of brain injury in hydrocephalus.  相似文献   

11.
12.
细胞因子在ARDS发病机制中的作用   总被引:10,自引:0,他引:10  
细胞因子是由多种细胞产生的多肽或低分子糖蛋白,在人体内含量极微,在pg水平就发挥作用。作为特异性免疫反应和非特异性免疫反应的蛋白质,细胞因子以自分泌、旁分泌、或内分泌方式产生,与相应的细胞表面受体结合,在局部或全身发挥复杂的生物学效应,它们的代谢异常和疾病的发生、发展有着密切的关系。有些细胞因子已应用于临床的生物学治疗,具有深远的临床应用价值,故对细胞因子的研究将是一个越来越重要的课题。急性肺损伤(ALI)/急性呼吸窘迫综合征(ARDS)发病机制错综复杂,大量临床和实验室研究证明多种效应细胞释放的炎症介质是造成ARDS的"中心环节",其中TNF-α、IL-1、IL-8、IL-10、CXC趋化因子等细胞因子在ARDS发病中的作用尤为重要。本文就细胞因子在ARDS发病机制中的作用做一综述。  相似文献   

13.
Summary The permeability of the choroid plexus and renal glomerulus to intravenously injected native, anionic ferritin and various cationic ferritin derivatives was studied in normal rats by electron microscopy. In both structures, anionic, native ferritin was largely confined to the circulatory compartment while the cationic forms penetrated and accumulated within the filtration barriers. In the choroid plexus, cationic ferritin concentrated in relationship to the endothelial fenestrations and the subendothelial basal lamina region. In the glomerulus, there was also an inner concentration of cationic tracer and, in addition, an aggregation of tracer along the outer, subepithelial portion of the basal lamina. The results indicate that the localization of tracer within the filtration barrier of both the choroid plexus and renal glomerulus is directly related to the tracer's isoelectric point. The findings suggest that the choroid plexus, like the glomerulus, contains fixed anionic groups within the capillary wall which influence its permeability.  相似文献   

14.
Several experimental and computational studies have investigated the effect of bone fragment impact on the spinal cord during trauma. However, the effect of the impact velocity of a fragment generated by a burst fracture on the stress and strain inside the spinal cord has not been computationally investigated, even though spinal canal occlusion and peak pressure at various impact velocities were provided in experimental studies. These stresses and strains are known factors related to clinical symptoms or injuries. In this study, a fluid-structure interaction model of the spinal cord, dura mater, and cerebrospinal fluid was developed and validated. The von-Mises stress distribution in the cord, the longitudinal strain, the cord compression and cross-sectional area at the impact center, and the obliteration of the cerebrospinal fluid layer were analyzed for three pellet sizes at impact velocities ranging from 1.5 m/s to 7.5 m/s. The results indicate that stress in the cord was substantially elevated when the initial impact velocity of the pellet exceeded a threshold of 4.5 m/s. Cord compression, reduction in cross-sectional area, and obliteration of the cerebrospinal fluid increased gradually as the velocity of the pellet increased, regardless of the size of the pellet. The present study provides insight into the mechanisms underlying spinal cord injury.  相似文献   

15.
Levels of neuron-specific enolase (NSE) were measured in rat CSF following occlusion of the four major arteries to the brain for 10, 20, or 30 min. In the CSF of rats submitted to 30 min of total ischemia, an up to nine-fold increase of NSE level occurred within the first few hours and then slowly diminished. Significant levels were seen for as long as 8 days. Histological observations 3 days after ischemia showed neuronal loss as well as neuronal damage in several forebrain regions such as hippocampus, striatum, and thalamus. Ischemia was followed by transient decreases in exploration behavior and neurological states that were no longer visible 24 h later. After 10 or 20 min ischemia, NSE levels were increased to a lesser degree and fewer damaged neurons were observed. The positive correlation between duration of ischemia and amount of NSE release in CSF indicates that the measurement of NSE in the CSF is a sensitive and reliable index of neuronal lesions.  相似文献   

16.
Following a recent report that epithelial cells of the choroid plexus possess histamine H2 receptors, the effect of cimetidine and ranitidine, histamine H2 receptor antagonists, on the secretion and electrolyte content of CSF was examined. Fifty cats were divided into one control (n = 6) and six experimental groups. CSF was collected by puncture of the cisterna magna following pentobarbital anesthesia, and its volume, concentrations of Na+, K+, Cl-, and pH were determined. Cimetidine or ranitidine (50, 20, or 10 mg/kg) was injected intravenously 2 h after the start of the test, and their concentrations were measured in hourly blood samples and in 30-min aliquots of CSF in the 50 mg/kg experimental groups. Whereas the secretion of CSF did not change over 6 h in the control group, it decreased significantly by 30-60 min after injection of cimetidine or ranitidine and remained low for the following 6 1/2 h in all experimental groups except the 10-mg ranitidine group. Peak cimetidine and ranitidine concentrations in CSF in the 50-mg experimental groups were noted 60 and 90 min, respectively, after intravenous injection. CSF electrolyte concentrations and pH did not change during the test in any group. We conclude that intravenous cimetidine or ranitidine can significantly reduce CSF secretion in the cat, possibly by competitive inhibition of the histamine effect on H2 receptors located on the choroid plexus epithelial cell, or by a direct effect on the capillaries of the choroid plexus.  相似文献   

17.
The serotonin metabolite 5-hydroxytryptophol was studied in human cerebrospinal fluid. A minor fraction (approximately 13%) was found in conjugated form from which it was liberated by treatment with sulphatase containing beta-glucuronidase activity. A concentration gradient of 5-hydroxytryptophol concentration was shown on lumbar tapping and the concentration in ventricular CSF was about 2.5 times higher than that in lumbar CSF. 5-Hydroxytryptophol and 5-hydroxyindoleacetic acid concentrations were significantly correlated in healthy, psychotic, and depressed subjects, but not in alcoholics. 5-Hydroxytryptophol concentrations in CSF of psychotic and depressed subjects were not different from those of healthy controls (4.22 pmol/ml +/- 0.15, SEM). In healthy subjects, hereditary factors seemed to have little influence on the CSF level of 5-hydroxytryptophol.  相似文献   

18.
The transfer coefficients (Kin) for the uptake of gallium-67 (67Ga) into brain and CSF were determined in unanesthetized male Fischer-344 rats fed either a normal or a low-Ca diet. Kin for 67Ga was also compared with transfer coefficients for the uptake of iron-55 (55Fe) and 125I-albumin in control animals. The value of CSF 67Ga Kin was 3 x 10(-7) ml.g-1.s-1 and was 50% larger in low-Ca animals. Brain regional Kin values for 67Ga were 3-9 x 10(-7) ml.g-1.s-1 with no differences in Kin between normal and low-Ca rats. CSF Kin values for 55Fe were 40% and those for albumin were 15% of Kin for 67Ga. For brain, Kin values for 55Fe were 15-40% smaller than for 67Ga, but for albumin the Kin values were 85% less than for 67Ga. 67Ga was found to be 99% bound to plasma proteins, whereas 55Fe was 99.9% bound. The results indicate that metals that are primarily bound to transferrin enter the CSF and brain very slowly. Uptake of both metals was faster than albumin, which may indicate that metal bound to small chelates contributes significantly to brain uptake. In addition, Ca deficiency does not enhance entry of Ga into the brain.  相似文献   

19.
(1)H NMR spectroscopy of cerebrospinal fluid (CSF) is currently being used to study metabolic profiles characteristic of distinct multiple sclerosis (MS) manifestations. For select MS patient groups, we have previously detected significantly increased concentrations of several identified metabolites and one unidentified compound. We now present, for the first time, the identification of the latter molecule, beta-hydroxyisobutyrate (BHIB). A combination of dedicated 1D and 2D (1)H NMR experiments was employed for signal assignment. To our knowledge, BHIB has not previously been identified in (1)H NMR spectra of biofluids or biological tissues. Our assignment suggests new biochemical pathways involved in specific MS pathologies.  相似文献   

20.
为了探讨丙戊酸钠(valproic acid,VPA)对急性呼吸窘迫综合征(acute respiratory distress syndrome,ARDS)小鼠治疗作用及分子机制,本研究将30只雌性C57BL/6小鼠分为空白组、LPS组、LPS+VPA组,LPS+VPA组小鼠造模前腹腔预注射VPA,以LPS气管内注射诱导ARDS小鼠模型,6 h后检测各组小鼠肺水肿(湿重/干重),检测各组小鼠血液SOD和MDA水平;通过ELISA检测各组小鼠肺泡灌洗液中TNFα和IL-1β水平,Western blotting检测各组小鼠NF-κB p65和p-H2A.X蛋白表达水平。研究结果表明:与空白组相比,LPS组小鼠肺水肿显著升高,与LPS组比较,LPS+VPA组和阳性组小鼠肺水肿显著降低,差异具有统计学意义(p<0.01)。ELISA结果显示,与空白组比较,LPS组小鼠肺组织TNFα和IL-1β含量显著升高,与LPS组比较,LPS+VPA组小鼠肺组织TNFα和IL-1β含量显著降低,差异具有统计学意义(p<0.01)。与空白组比较,LPS组小鼠血液SOD活性显著降低,MDA含量显著升高,与LPS组比较,LPS+VPA组和阳性组小鼠血液SOD活性显著升高,MDA含量显著降低。Western blotting结果显示,与空白组比较,LPS组小鼠肺NF-κB p65和p-H2A.X蛋白表达显著升高,与LPS组比较,LPS+VPA组和阳性组小鼠肺NF-κB p65和p-H2A.X蛋白表达显著降低,差异具有统计学意义(p<0.01)。本研究初步表明:VPA能够抑制NF-κB通路,抑制小鼠氧化应激和炎症反应,保护ARDS小鼠肺组织。  相似文献   

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