rat brain Dotaz Zobrazit nápovědu
Manganese retention was observed in brains and in several other tissues of female Wistar rats after the intratracheal instillation of an inorganic manganese compound: manganese dioxide. Two categories of rats, younger (180 to 200g) and older (330 to 350g), were divided into a control group, in which animals received vehicle only (0.5 mL physiological saline), and an experimental group, in which rats received a dose of 0.48 mg of Mn/kg body weight (in 0.5 mL saline), twice a week for 3 months, for a total dosage of 11.80 mg of Mn/kg body weight. At the end of the exposure period, manganese retention in selected rat organs, brain, liver, kidney, and lung, was analyzed using atomic absorption spectrophotometry. At the end of the 6-wk or 12-wk manganese dioxide exposure period, analysis of variance of the manganese retention results revealed significant differences between Mn-exposed and unexposed rats in brain, kidney, and lung tissues (p<0.01) for both experimental age categories. Moreover, at the end of the 12-wk exposure period, significant results (p<0.05) between younger and older rats were obtained for both brain and kidneys. In both types of tissue, the manganese retention in the younger group was higher than that in older animals.
- MeSH
- intratracheální intubace MeSH
- krysa rodu Rattus MeSH
- mangan metabolismus MeSH
- mozek metabolismus MeSH
- orgánová specificita MeSH
- oxidy aplikace a dávkování MeSH
- potkani Wistar MeSH
- sloučeniny manganu aplikace a dávkování MeSH
- stárnutí metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- mangan MeSH
- manganese dioxide MeSH Prohlížeč
- oxidy MeSH
- sloučeniny manganu MeSH
Carnitine administration (by intraperitoneal injection) to 21-day-old-rats prevents the increase of thiobarbituric acid-reactive substances (index of lipid peroxidation and free radical damage) induced by 30 min hypobaric hypoxia in four different parts of the brain (cerebral cortex, subcortical structures, medulla oblongata and cerebellum).
- MeSH
- karnitin krev farmakologie MeSH
- krysa rodu Rattus MeSH
- látky reagující s kyselinou thiobarbiturovou metabolismus MeSH
- mozek - chemie účinky léků MeSH
- mozková hypoxie metabolismus MeSH
- peroxidace lipidů účinky léků MeSH
- potkani Wistar MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- karnitin MeSH
- látky reagující s kyselinou thiobarbiturovou MeSH
The aim of our study was to test the hypothesis, if melatonin pre-treatment (in dose of 100 mg/kg) can influence the changes of brain function after short-term hypoxia exposition (simulated altitude 9000 m) in young immature rats. Experiments were performed on freely moving 12-, 25- and 35-day-old male Wistar rats. One hour prior to hypoxia exposition, animals were pre-treated with melatonin and 24 hours after hypoxia cortical afterdischarges (ADs) were elicited by repeated stimulation of the right sensorimotor cortex. The duration of evoked ADs and shape of evoked graphoelements was monitored. Short-term exposure to hypoxic conditions resulted in significantly shorter ADs duration in 12-day-old rats after stimulations (except the 2nd one stimulation) compared to control group. Administration of melatonin prolonged the duration of ADs after all stimulations except the 1st one. Analysis of the duration ADs revealed no significant changes, either after the exposition to hypobaric hypoxia or after melatonin administration in 25- and 35-day-old animals. Effects and mechanisms of melatonin action on the brain seizure susceptibility and the possible beneficial role of that treatment in hypoxic brain damage are discussed.
- MeSH
- akční potenciály účinky léků MeSH
- elektrokardiografie účinky léků MeSH
- krysa rodu Rattus MeSH
- melatonin aplikace a dávkování MeSH
- mozek účinky léků patofyziologie MeSH
- mozková hypoxie patofyziologie MeSH
- nervová síť účinky léků patofyziologie MeSH
- potkani Wistar MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- melatonin MeSH
The authors studied the morphological picture of implanted foetal brain tissue. Macroscopically, they found that the grafts used for morphological study had taken in every case and that the size of the graft had doubled or trebled. The surface of the implant grew above the level of the recipient's cortex and numerous branching blood vessels were observed in the graft-cortex contact area. In the light microscope, organization of the cells in circular clusters or strips was found in the implant. Large numbers of blood vessels of varying calibre were present in the vicinity of large cell concentrations. Distinct differences between the cytoarchitectonics of the normal tissue of the recipient and the graft tissue were seen. Cells with a normal appearance or an apolar form, whose nucleus contained irregularly scattered chromatin and mosaic-like nucleoli, were observed at ultrastructural level. The nuclear membrane was thrown into multiple folds which invaginated deep into the nuclear matter. The Golgi complex covered a large area. Axodendritic synapses indistinguishable from the control were found in the neuropil. No changes were observed in the walls of the capillaries. The pericapillary zone was characterized by the presence of light astrocyte processes.
PURPOSE: Reliable detection and fitting of macromolecules (MM) are crucial for accurate quantification of brain short-echo time (TE) 1 H-MR spectra. An experimentally acquired single MM spectrum is commonly used. Higher spectral resolution at ultra-high field (UHF) led to increased interest in using a parametrized MM spectrum together with flexible spline baselines to address unpredicted spectroscopic components. Herein, we aimed to: (1) implement an advanced methodological approach for post-processing, fitting, and parametrization of 9.4T rat brain MM spectra; (2) assess the concomitant impact of the LCModel baseline and MM model (ie, single vs parametrized); and (3) estimate the apparent T2 relaxation times for seven MM components. METHODS: A single inversion recovery sequence combined with advanced AMARES prior knowledge was used to eliminate the metabolite residuals, fit, and parametrize 10 MM components directly from 9.4T rat brain in vivo 1 H-MR spectra at different TEs. Monte Carlo simulations were also used to assess the concomitant influence of parametrized MM and DKNTMN parameter in LCModel. RESULTS: A very stiff baseline (DKNTMN ≥ 1 ppm) in combination with a single MM spectrum led to deviations in metabolite concentrations. For some metabolites the parametrized MM showed deviations from the ground truth for all DKNTMN values. Adding prior knowledge on parametrized MM improved MM and metabolite quantification. The apparent T2 ranged between 12 and 24 ms for seven MM peaks. CONCLUSION: Moderate flexibility in the spline baseline was required for reliable quantification of real/experimental spectra based on in vivo and Monte Carlo data. Prior knowledge on parametrized MM improved MM and metabolite quantification.
- Klíčová slova
- 1H-MRS, UHF, baseline, fitting, macromolecules, parametrization, rat brain, relaxation times,
- MeSH
- krysa rodu Rattus MeSH
- makromolekulární látky metabolismus MeSH
- mozek - chemie * MeSH
- mozek * diagnostické zobrazování metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Názvy látek
- makromolekulární látky MeSH
The lipid composition of the brain is of great importance to its metabolism and function. Although much research has been done on regional brain lipid composition, studies usually suffer from limited brain regions or from limited lipids analyzed. We modified a previously described method for the separation of brain phospholipids and glycolipids, improving the separation and sensitivity of the method. Using this modified method, we measured the lipid composition of the frontal and entorhinal cortices, the hippocampus, basal ganglia, cerebellum, and medulla oblongata of five rats under nitrous oxide analgesia. Total lipid content was highest (p < 0.05) in the medulla oblongata (111.0 +/- 6.0 mg/g wet brain, X +/- SD) followed by the hippocampus (72.6 +/- 2.8), cerebellum (62.7 +/- 4.6), basal ganglia (62.6 +/- 1.5), frontal cortex (57.7 +/- 2.1), and entorhinal cortex (53.3 +/- 1.9). The areas with higher total lipid content (p < 0.05) also had higher percentages of cerebrosides (18.6 +/- 2.2 in the medulla oblongata vs 8.3 +/- 1.2 in the frontal cortex) and 40 to 50% lower levels of phosphatidylcholine and phosphatidylinositol. The relation between the ratio of cerebrosides plus sulfatides to phosphatidylcholine and the total lipid content indicates that differences in brain lipid composition between regions are attributable to their relative gray/white matter content.
- MeSH
- cholesterol metabolismus MeSH
- chromatografie na tenké vrstvě MeSH
- denzitometrie MeSH
- fosfolipidy metabolismus MeSH
- glykolipidy metabolismus MeSH
- krysa rodu Rattus MeSH
- metabolismus lipidů * MeSH
- mozek - chemie fyziologie MeSH
- potkani Wistar MeSH
- vysokoúčinná kapalinová chromatografie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, U.S. Gov't, P.H.S. MeSH
- Názvy látek
- cholesterol MeSH
- fosfolipidy MeSH
- glykolipidy MeSH
Magnetic resonance spectroscopic imaging (MRSI) enables the simultaneous noninvasive acquisition of MR spectra from multiple spatial locations inside the brain. Although 1H-MRSI is increasingly used in the human brain, it is not yet widely applied in the preclinical setting, mostly because of difficulties specifically related to very small nominal voxel size in the rat brain and low concentration of brain metabolites, resulting in low signal-to-noise ratio (SNR). In this context, we implemented a free induction decay 1H-MRSI sequence (1H-FID-MRSI) in the rat brain at 14.1 T. We combined the advantages of 1H-FID-MRSI with the ultra-high magnetic field to achieve higher SNR, coverage, and spatial resolution in the rat brain and developed a custom dedicated processing pipeline with a graphical user interface for Bruker 1H-FID-MRSI: MRS4Brain toolbox. LCModel fit, using the simulated metabolite basis set and in vivo measured MM, provided reliable fits for the data at acquisition delays of 1.30 ms. The resulting Cramér-Rao lower bounds were sufficiently low (< 30%) for eight metabolites of interest (total creatine, N-acetylaspartate, N-acetylaspartate + N-acetylaspartylglutamate, total choline, glutamine, glutamate, myo-inositol, and taurine), leading to highly reproducible metabolic maps. Similar spectral quality and metabolic maps were obtained with one and two averages, with slightly better contrast and brain coverage due to increased SNR in the latter case. Furthermore, the obtained metabolic maps were accurate enough to confirm the previously known brain regional distribution of some metabolites. The acquisitions proved high reproducibility over time. We demonstrated that the increased SNR and spectral resolution at 14.1 T can be translated into high spatial resolution in 1H-FID-MRSI of the rat brain in 13 min using the sequence and processing pipeline described herein. High-resolution 1H-FID-MRSI at 14.1 T provided robust, reproducible, and high-quality metabolic mapping of brain metabolites with minimal technical limitations.
- Klíčová slova
- 1H‐FID‐MRSI, brain metabolites, magnetic resonance spectroscopic imaging, metabolite mapping, rat brain, ultra‐high field,
- MeSH
- krysa rodu Rattus MeSH
- magnetická rezonanční tomografie metody MeSH
- metabolom MeSH
- mozek * metabolismus diagnostické zobrazování MeSH
- poměr signál - šum MeSH
- potkani Sprague-Dawley MeSH
- potkani Wistar MeSH
- protonová magnetická rezonanční spektroskopie metody MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
T-2 toxin, a trichothecene mycotoxin, is a common contaminant in food and animal feed, and is also present in processed cereal products. The most common route of T-2 toxin exposure in humans is through dietary ingestion. The cytotoxic effects of T-2 toxin include modifications to feeding behavior, nervous disorders, cardiovascular alterations, immunosuppression, and hemostatic derangements. However, to date, effects on the central nervous system (CNS) have rarely been reported. In the present study, female Wistar rat were given a single dose of T-2 toxin at 2 mg/kg b.w. and were sacrificed at one, three, and seven days post-exposure. Histopathological analysis and transmission electron microscope (TEM) observations were used to investigate injury to the brain and pituitary gland. Damage to the brain and pituitary at the molecular level was detected by real time-polymerase chain reaction (RT-PCR), western blot, and immunohistochemical assays. Liquid chromatograph-mass spectrometer/mass spectrometer (LC-MS/MS) was used to investigate T-2 concentration in the brain. The results showed that pathological lesions were obvious in the brain at three days post-exposure; lesions in the pituitary were not observed until seven days post-exposure. Autophagy in the brain and apoptosis in the pituitary suggest that T-2 toxin may induce different acute reactions in different tissues. Importantly, low concentrations of T-2 toxin in the brain were observed in only one rat. Responsible for the above mentioned, we hypothesize that brain damage caused by this toxin may be due to the ability of the toxin to directly cross the blood-brain barrier (BBB). Therefore, given its widespread pollution in food, we should pay more attention to the neurotoxic effects of the T-2 toxin, which may have widespread implications for human health.
- Klíčová slova
- T-2 toxin, brain, human health, hypophysis, neurotoxicity,
- MeSH
- apoptóza účinky léků MeSH
- autofagie účinky léků MeSH
- časové faktory MeSH
- chování zvířat účinky léků MeSH
- chromatografie kapalinová MeSH
- hematoencefalická bariéra metabolismus MeSH
- hodnocení rizik MeSH
- hypofýza účinky léků metabolismus ultrastruktura MeSH
- imunohistochemie MeSH
- kapilární permeabilita MeSH
- kvantitativní polymerázová řetězová reakce MeSH
- mozek účinky léků metabolismus ultrastruktura MeSH
- neurotoxické syndromy etiologie metabolismus patologie psychologie MeSH
- potkani Wistar MeSH
- regulace genové exprese MeSH
- T-2 toxin metabolismus toxicita MeSH
- tandemová hmotnostní spektrometrie MeSH
- transmisní elektronová mikroskopie MeSH
- western blotting MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- T-2 toxin MeSH
In unfixed cryostat sections of the brains of early postnatal and adult rats, we screened for cells containing vimentin-positive intermediate filaments (VI+-IFs) by applying a panel of four monoclonal antibodies (Mabs VI-01, VI-02, VI-05 and VI-5B3) using indirect immunofluorescence. All of the Mabs stained VI+-IFs in the stromal part of the choroid plexus, in endothelial cells of blood vessels and in meninges in both adult and immature brains, although with varying strength (VI-5B3 and VI-01 stained more strongly than VI-05 and VI-02). In the brain parenchyma of adults, intense staining was mainly localized in ventricular ependymal cells (VI-5B3/VI-01 greater than VI-02/VI-05) and fibrous astrocyte-like cells (FAs). In the immature brain, the ependymal cells were activated in appearance, with evidence of cell enlargement, greater spreading of VI+-IFs within the cytoplasm and more pronounced VI+ cytoplasmic protrusions into the brain parenchyma. VI+-FAs were found near the ependymal and meningeal borders as well as in the white matter tracts of adult brain (VI-5B3/VI-01 greater than VI-05 greater than VI-02). In immature animals, VI+-FAs were less frequently encountered in the forebrain regions, except in and near the subepenydmal layer (in the adjacent parenchyma) as well as in submeningeal layers. Weaker staining was usually elicited by Mabs VI-02 and VI-05. In the cerebellum, Bergmann cell fibers were stained in both age groups. In adults, the most intense fluorescence usually occurred in segments close to the pia (VI-5B3/VI-01 greater than VI-05 greater than VI-02).(ABSTRACT TRUNCATED AT 250 WORDS)
- MeSH
- astrocyty metabolismus MeSH
- fluorescenční protilátková technika MeSH
- imunohistochemie MeSH
- inbrední kmeny potkanů MeSH
- krysa rodu Rattus MeSH
- monoklonální protilátky MeSH
- mozek anatomie a histologie metabolismus MeSH
- vimentin imunologie metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- monoklonální protilátky MeSH
- vimentin MeSH
Several studies have established that increased cerebrospinal fluid (CSF) levels of quinolinic acid (QUIN), a macrophage/microglia-derived excitotoxin with N-methyl-D-aspartate (NMDA)-receptor affinity, may reflect abnormal blood-brain barrier (BBB) function in patients with acquired immunodeficiency syndrome (AIDS) dementia complex, exhibiting a relationship to their clinical and neurological status. This study was aimed to evaluate whether QUIN (250 nmol/0.25 microl/ventricle) infused into both lateral cerebral ventricles permeates adult rat brain microvessels to plasma albumin. Possible BBB dysfunction was examined 4 days after the intracerebroventricular (i.c.v.) infusion of QUIN by measuring plasma albumin extravasation using rocket immunoelectrophoresis. The i.c.v. infusion of QUIN failed to increase the extracellular tissue concentration of albumin in the entorhinal cortex, but significantly higher levels were found in the hippocampus proper (but not in the subiculum region and dentate gyrus) and in the striatum. To evaluate the possible relationship between plasma protein extravasation and QUIN-induced tissue necrosis, we quantified neuronal death in the rat hippocampal formation (subiculum, CA1/CA3 areas of the hippocampus proper, dentate gyrus). We found significantly higher tissue levels of plasma albumin in the hippocampus proper, in which the CA1 area exhibited the highest neuronal loss while the low rate of neuronal death was not accompanied by significant albumin extravasation in the dentate gyrus. However, in case of the subiculum, in which the neuronal loss reached comparable values to those in the CA1 area, we did not find significant enhancement of plasma albumin leakage into this area. The regional differences in brain microvascular permeability may depend on the density of NMDA receptors in the multicellular capillary barrier, but the differences in neuronal death may also reflect an involvement of NMDA receptors in neuronal membranes. We conclude that increased CSF QUIN levels evoke a dysfunction of the BBB that may only partially be related to sites with pronounced neuronal damage in the rat brain regions susceptible to NMDA-receptor mediated toxicity.
- MeSH
- buněčná smrt účinky léků MeSH
- hematoencefalická bariéra účinky léků fyziologie MeSH
- hipokampus krevní zásobení cytologie účinky léků MeSH
- kapilární permeabilita účinky léků fyziologie MeSH
- krysa rodu Rattus MeSH
- kyselina chinolinová aplikace a dávkování toxicita MeSH
- mikrocirkulace účinky léků fyziologie MeSH
- mozkové komory účinky léků fyziologie MeSH
- nekróza MeSH
- neurony cytologie účinky léků fyziologie MeSH
- parenterální infuze MeSH
- potkani Wistar MeSH
- sérový albumin metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- kyselina chinolinová MeSH
- sérový albumin MeSH