Search results for "Ley"
showing 10 items of 1218 documents
Effects of obesity on periodontal tissue remodeling during orthodontic movement.
2021
Made available in DSpace on 2021-06-25T15:01:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-04-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) German Research Foundation (DFG) Introduction: Orthodontic movement triggers a sequence of cellular and molecular events that may be affected by different systemic conditions. This study evaluated the effect of obesity on rat periodontal tissue remodeling induced by mechanical orthodontic force. Methods: Thirty-two Holtzman rats were distributed into 4 groups: control, obesity induction (O), orthodontic movement (M), and obesity induction and orthodontic movement (OM). Obesity was induced by a high-fat diet for 90 days. Af…
Induction of c-fos gene expression by the selective sigma receptor ligand EMD 57445 in rat brain.
1996
Based on animal studies it has been reasoned that ligands to sigma binding sites might be effective in the treatment of schizophrenic disorders and may also be used to investigate this largely elusive disorder on a molecular level. Expression patterns of c-fos in rat brain were studied following treatment with single doses of the sigma ligand EMD 57445 (0.3, 1, 3, 30 mg/kg s.c.). Specific c-fos gene expression was detected at all concentrations tested in various cortical areas. The signals observed were dose-dependent with the highest intensities in the piriform cortex. Strong signals were also detected in hippocampal areas CA 1,2,3 and the gyrus dentatus, as well as in the medial habenula …
Chronical haloperidol and clozapine treatment in rats: Differential RNA display analysis, behavioral studies and serum level determination
1998
1. Adult, female rats were treated orally for 23 days with 1.6 mg/kg haloperidol or 36 mg/kg clozapine per day, to study chronic effects of the two neuroleptics. 2. At five time points during the neuroleptic treatment, animal behavior was recorded in an open field and locomotive activity was analysed. At the end of the experiment, rats were decapitated, blood samples were collected and serum concentrations of haloperidol and clozapine were determined by a radioreceptor or HPLC assay, respectively. RNA was isolated from each brain, without cerebellum, and subjected to differential RNA display. 3. Mean serum concentrations were 8 ng/ml for haloperidol and 21 ng/ml for clozapine. Analysis of o…
Viability and function of the cryopreserved whole rat ovary: comparison between slow-freezing and vitrification
2011
Objective To investigate four different protocols for cryopreservation of the whole rat ovary with intact vasculature to evaluate whether differences exist in post-thawing viability of the ovary after either vitrification or slow freezing. Design Experimental study. Setting Obstetrics and gynecology department. Animal(s) Immature Sprague-Dawley female rats. Intervention(s) Ovaries were isolated with the vascular tree intact up to the bifurcation of the abdominal aorta and were subsequently cannulated. The ovaries were flushed with increasing concentrations of the cryoprotectant dimethyl sulfoxide (DMSO) to either 1.5 or 7 M. The ovaries underwent cryopreservation by vitrification or passive…
Calcium Dependence of the Mechanical Response Evoked by Okadaic Acid in Smooth Muscle
1995
The effects of okadaic acid (OA), obtained from a culture of the marine dinoflagellate Prorocentrum Lima were studied on isolated strips of rat myometrium. The contractile response evoked by OA at 5, 10, and 20 μM in normal physiological solution was unaffected in the presence of tetrodotoxin (10 μM), indomethacin (3 μM), or a cocktail of antagonists which blocked muscarinic, adrenergic, histaminergic, serotonergic, and opioid receptors. Similarly, the response to OA was unaffected in the presence of nifedipine at a concentration (1 μM) which completely or highly blocked the response to KCl (60 mM), oxytocin (1 μM), or acetylcholine (100 μM). In a Ca 2+ -free 1 mM EGTA-containing solution, …
Progressive pulmonary fibrosis is mediated by TGF-β isoform 1 but not TGF-β3
2007
Tissue repair is a well-orchestrated biological process involving numerous soluble mediators, and an imbalance between these factors may result in impaired repair and fibrosis. Transforming growth factor (TGF)-beta is a key profibrotic element in this process and it is thought that its three isoforms act in a similar way. Here, we report that TGF-beta3 administered to rat lungs using transient overexpression initiates profibrotic effects similar to those elicited by TGF-beta1, but causes less severe and progressive changes. The data suggest that TGF-beta3 does not lead to inhibition of matrix degradation in the same way as TGF-beta1, resulting in non-fibrotic tissue repair. Further, TGF-bet…
Neurochemistry of identified motoneurons of the tensor tympani muscle in rat middle ear
2008
The objective of the present study was to identify efferent and afferent transmitters of motoneurons of the tensor tympani muscle (MoTTM) to gain more insight into the neuronal regulation of the muscle. To identify MoTTM, we injected the fluorescent neuronal tracer Fluoro-Gold (FG) into the muscle after preparation of the middle ear in adult rats. Upon terminal uptake and retrograde neuronal transport, we observed FG in neurons located lateral and ventrolateral to the motor trigeminal nucleus ipsilateral to the injection site. Immunohistochemical studies of these motoneurons showed that apparently all contained choline acetyltransferase, demonstrating their motoneuronal character. Different…
Transplantation of Mesenchymal Stem Cells Exerts a Greater Long-Term Effect than Bone Marrow Mononuclear Cells in a Chronic Myocardial Infarction Mod…
2010
The aim of this study is to assess the long-term effect of mesenchymal stem cells (MSC) transplantation in a rat model of chronic myocardial infarction (MI) in comparison with the effect of bone marrow mononuclear cells (BM-MNC) transplant. Five weeks after induction of MI, rats were allocated to receive intramyocardial injection of 106 GFP-expressing cells (BM-MNC or MSC) or medium as control. Heart function (echocardiography and 18F-FDG-microPET) and histological studies were performed 3 months after transplantation and cell fate was analyzed along the experiment (1 and 2 weeks and 1 and 3 months). The main findings of this study were that both BM-derived populations, BM-MNC and MSC, ind…
Corticotropin-Releasing Hormone-Mediated Induction of Intracellular Signaling Pathways and Brain-Derived Neurotrophic Factor Expression Is Inhibited …
2005
CRH receptor (CRHR) 1 and the cannabinoid receptor 1 (CB1) are both G protein-coupled receptors. Activation of CRHR1 leadstoincreasesincAMPproductionandphosphorylationof the transcription factor cAMP response element-binding protein (CREB). In contrast, CB1 is negatively coupled to the cAMP signaling cascade. In this study, we analyzed a putative interaction between these two systems focusing on the regulation of the expression of brain-derived neurotrophic factor (BDNF), a CREB-regulated gene. In situ hybridization revealed coexpression of CRHR1 and CB1 receptors in the granular layer of the cerebellum. Therefore, we analyzed the effects of CRH and the CB1 agonist WIN-55,212-2 on BDNF expr…
The nicotinic acetylcholine receptor agonist (±)-epibatidine increases FGF-2 mRNA and protein levels in the rat brain
2000
Abstract In a previous work, we showed that acute intermittent nicotine treatment up-regulates the level of fibroblast growth factor-2 (FGF-2) mRNA in brain regions of tel- and mesencephalon of rats suggesting that neuroprotective effect of (−)nicotine may, at least in part, involve an activation of the neuronal FGF-2 signalling. The present experiments were designed to extend the study on the nicotinic receptor mediated up-regulation of FGF-2 mRNA levels to the use of the potent nicotinic acetylcholine receptor (nAChR) agonist (±)-epibatidine. The (±)-epibatidine treatment led to a strong and long lasting up-regulation of FGF-2 mRNA expression in the cerebral cortex, in the hippocampal for…