Search results for "MESH: Rats"
showing 10 items of 21 documents
Olfactory bulbectomy, but not odor conditioned aversion, induces the differentiation of immature neurons in the adult rat piriform cortex.
2011
International audience; The piriform cortex layer II of young-adult rats presents a population of prenatally generated cells, which express immature neuronal markers, such as the polysialylated form of the neural cell adhesion molecule (PSA-NCAM) or doublecortin (DCX), and display structural characteristics of immature neurons. The number of PSA-NCAM/DCX expressing cells in this region decreases markedly as age progresses, suggesting that these cells differentiate or die. Since the piriform cortex receives a major input from the olfactory bulb and participates in olfactory information processing, it is possible that the immature neurons in layer II are affected by manipulations of the olfac…
Long-term moderate magnesium-deficient diet shows relationships between blood pressure, inflammation and oxidant stress defense in aging rats
2006
International audience; Epidemiological and experimental studies have indicated a relationship among aging, dietary Mg, inflammatory stress, and cardiovascular disease. Our aim in the present study was to investigate possible links between dietary Mg, oxidant stress parameters, and inflammatory status with aging in rats. We designed a long-term study in which rats were fed for 22 months with moderately deficient (150 mg/kg), standard (800 mg/kg), or supplemented (3200 mg/kg) Mg diets. Comparisons were made with young rats fed with the same diets for 1 month. Compared to the standard and supplemented diets, the Mg-deficient diet significantly increased blood pressure, plasma interleukin-6, f…
Effects of manganese injected into rat nostrils: implications for in vivo functional study of olfaction using MEMRI.
2011
WOS: 000298212500007; International audience; Manganese-enhanced magnetic resonance imaging (MEMRI) is a powerful tool for visualizing neuronal pathways and mapping brain activity modulation. A potential drawback of MEMRI lies in the toxic effects of manganese (Mn), which also depend on its administration route. The aim of this study was to analyze the effects of Mn doses injected into the nostrils of rats on both olfactory perception and MRI contrast enhancement. For this purpose, doses in the range 0-8 μmol MnCl(2) were tested. Behavioral items were quantified with and without odor stimulation during the first 2 h following Mn injection. The MRI study was performed after 16 h of intermitt…
Growth hormone potentiates thyroid hormone effects on post-exercise phosphocreatine recovery in skeletal muscle.
2012
International audience; OBJECTIVE: The aim of the study was to determine the respective impact of thyroxine and growth hormone on in vivo skeletal mitochondrial function assessed via post exercise phosphocreatine recovery. DESIGN: The hind leg muscles of 32 hypophysectomized rats were investigated using (31)P nuclear magnetic resonance spectroscopy at rest and during the recovery period following a non tetanic stimulation of the sciatic nerve. Each rat was supplemented with hydrocortisone and was randomly assigned to one of the 4 groups: the group Hx was maintained in hypopituitarism., the group HxT was treated with 1 μg/100g/day of thyroxine (T4), the group HxG with 0.2 IU/kg/day of recomb…
Oral homeostasis disruption by medical plasticizer component bisphenol A in adult male rats.
2013
Objectives/Hypothesis Bisphenol A (BPA) is a synthetic estrogen-like chemical mimetic widely used in the manufacture of polycarbonate plastics and epoxy resins found in numerous consumer products including food packaging, medical devices, and dental sealants. Because it is recovered in fluids and it can reach high levels in saliva, this study aimed to evaluate its safety on oral homeostasis by examining its effects on salivary glands, mouth epithelium, water consumption, and salt preference, each parameter being estrogen sensitive. Study Design Randomized controlled trial involving rats. Methods A dose-response study was conducted in adult Wistar rats randomized into five groups (n = 12). B…
Expression and differential localization of xenobiotic transporters in the rat olfactory neuro-epithelium.
2011
International audience; Transporters, such as multidrug resistance P-glycoproteins (MDR), multidrug resistance-related proteins (MRP) and organic anion transporters (OATs), are involved in xenobiotic metabolism, particularly the cellular uptake or efflux of xenobiotics (and endobiotics) or their metabolites. The olfactory epithelium is exposed to both inhaled xenobiotics and those coming from systemic circulation. This tissue has been described as a pathway for xenobiotics to the brain via olfactory perineural space. Thereby, olfactory transporters and xenobiotic metabolizing enzymes, dedicated to the inactivation and the elimination of xenobiotics, have been involved in the toxicological p…
Abnormalities of mitochondrial functioning can partly explain the metabolic disorders encountered in sarcopenic gastrocnemius.
2007
International audience; Aging triggers several abnormalities in muscle glycolytic fibers including increased proteolysis, reactive oxygen species (ROS) production and apoptosis. Since the mitochondria are the main site of substrate oxidation, ROS production and programmed cell death, we tried to know whether the cellular disorders encountered in sarcopenia are due to abnormal mitochondrial functioning. Gastrocnemius mitochondria were extracted from adult (6 months) and aged (21 months) male Wistar rats. Respiration parameters, opening of the permeability transition pore and ROS production, with either glutamate (amino acid metabolism) or pyruvate (glucose metabolism) as a respiration substr…
Effects of a high-fat diet on energy metabolism and ROS production in rat liver.
2011
International audience; BACKGROUND & AIMS: A high-fat diet affects liver metabolism, leading to steatosis, a complex disorder related to insulin resistance and mitochondrial alterations. Steatosis is still poorly understood since diverse effects have been reported, depending on the different experimental models used. METHODS: We hereby report the effects of an 8 week high-fat diet on liver energy metabolism in a rat model, investigated in both isolated mitochondria and hepatocytes. RESULTS: Liver mass was unchanged but lipid content and composition were markedly affected. State-3 mitochondrial oxidative phosphorylation was inhibited, contrasting with unaffected cytochrome content. Oxidative…
The impact of tumor nitric oxide production on VEGFA expression and tumor growth in a zebrafish rat glioma xenograft model.
2015
International audience; To investigate the effect of nitric oxide on tumor development, we established a rat tumor xenograft model in zebrafish embryos. The injected tumor cells formed masses in which nitric oxide production could be detected by the use of the cell-permeant DAF-FM-DA (diaminofluorophore 4-amino-5-methylamino-2'-7'-difluorofluorescein diacetate) and DAR-4M-AM (diaminorhodamine-4M). This method revealed that nitric oxide production could be co-localized with the tumor xenograft in 46% of the embryos. In 85% of these embryos, tumors were vascularized and blood vessels were observed on day 4 post injection. Furthermore, we demonstrated by qRT-PCR that the transplanted glioma ce…
Ventilatory conditioning by self-stimulation in rats: A pilot study
1994
International audience; This article describes an experimental attempt to condition breathing pattern in rats. In this experiment, a freely moving rat was first rewarded by an electrical stimulation of the medial forebrain bundle whenever inspiratory duration (TI) exceeded 300 ms. A bidirectional control was then used: TIs longer than 400 ms were rewarded, and then TIs shorter than 300 ms were rewarded. The frequency of TIs longer than 300 ms increased when this event was rewarded, further increased when TIs above 400 ms were rewarded, and decreased during reversal conditioning (TI < 300 ms). At the beginning of the experiment, stimulation caused increased arousal and motor activity, but af…