Search results for "RATS"
showing 10 items of 3537 documents
Suppression of ischemia-induced fos expression and AP-1 activity by an antisense oligodeoxynucleotide to c-fos mRNA.
1994
The molecular events of brain adaptation to injury that may underlie functional recovery after stroke remain largely undefined. Recent observations of altered gene expression in ischemic brain using animal stroke models have opened new avenues for exploration of the biochemical cascades after stroke [1–11]. These postischemic events include an increase in extracellular excitatory amino acid neurotransmitters such as glutamate. Glutamate receptor–mediated activation of phospholipases and protein kinases results in the alteration of nuclear regulatory processes, including the expression of immediate early genes such as c-fos, junB, and c-jun [5, 12]. The Fos, Jun, and JunB proteins have been …
Localization and mRNA steady-state level of cellular fibronectin in rat liver undergoing a CCl4-induced acute damage or fibrosis.
1993
Abstract In an attempt to investigate cellular fibronectin synthesis and deposition during acute liver damage and fibrogenesis, we used the presence of the additional type III-related ED-A domain of cellular fibronectin as a characteristic for distinguishing it from the plasma form. Using site-specific antibodies, we localized cellular fibronectin deposition in the necrotic pericentral areas of acutely damaged liver tissue after a single CCl 4 -gavage, whereas in control liver only trace amounts of cellular fibronectin were detectable along the sinusoids. Upon several CCl 4 -administrations leading to liver fibrosis, cellular fibronectin deposits were accumulated in the fibrotic septa. Nort…
Pancreatic T cell protein-tyrosine phosphatase deficiency ameliorates cerulein-induced acute pancreatitis.
2014
Background Acute pancreatitis (AP) is a common clinical problem whose incidence has been progressively increasing in recent years. Onset of the disease is trigged by intra-acinar cell activation of digestive enzyme zymogens that induce autodigestion, release of pro-inflammatory cytokines and acinar cell injury. T-cell protein tyrosine phosphatase (TCPTP) is implicated in inflammatory signaling but its significance in AP remains unclear. Results In this study we assessed the role of pancreatic TCPTP in cerulein-induced AP. TCPTP expression was increased at the protein and messenger RNA levels in the early phase of AP in mice and rats. To directly determine whether TCPTP may have a causal rol…
Characterization of cryopreserved rat liver parenchymal cells by metabolism of diagnostic substrates and activities of related enzymes
1992
The metabolism of testosterone and benzo(a)pyrene (BaP) which is mediated by diverse enzymes was determined in cryopreserved rat liver parenchymal cells and compared with that found in freshly isolated cells. In addition, the activities of single xenobiotic-metabolizing enzymes were measured by using specific substrates. The cytochrome P450 (P450)-mediated total metabolic conversion of testosterone was reduced to 55% in cryopreserved cells. The metabolite profile, i.e. the formation of single metabolites compared with total metabolic conversion, was however unchanged when compared with freshly isolated cells. A concomitant reduction in the activities of the involved P450 isoenzymes can ther…
Influence of disulfiram on oxidative drug demethylation.
1970
In clinical antiepileptie therapy it has been observed that the simultaneous administration of diphenylhydantoin and various other drugs causes toxic reactions to diphenylhydantoin. I t was found that disulfiram (Olesen, 1966) as well as ehloramphenieol (Christensen and Skovsted, 1969) cause toxic effects in patients treated with diphenylhydantoin. They are attributed to an increased concentration of diphenylhydantoin in the plasma. Analogous observations show that chloramphenieol enhances the clinical effects of tolbutamide and dicoumarol (Christensen and Skovsted, 1969). Since diphenylhydantoin is metabolized chiefly by p-hydroxylation to 5-(p-hydroxyphenyl)-5-phenyl-hydantoin (Butler, 19…
Identification and quantification of metabolite conjugates of activated cyclophosphamide and ifosfamide with mesna in urine by ion-pair extraction an…
1985
The high bladder toxicity of the alkylating oxazaphosphorine anticancer drugs, cyclophosphamide and ifosfamide is effectively reduced by the concomitant administration of mesna (sodium 2-mercaptoethane sulphonate). The formation and rapid urinary excretion of conjugates of the activated (4-hydroxylated) oxazaphosphorine metabolites with mesna has been suggested as the pharmacological basis for the selective detoxification, but separation and identification of such metabolites in vivo have been extremely difficult due to their high polarity and chemical lability. In this study an ion-pair extraction procedure in combination with positive and negative ion fast atom bombardment mass spectromet…
Metabolism of third generation synthetic cannabinoids using zebrafish larvae.
2021
Synthetic cannabinoids are the second largest group of new psychoactive substances reported by the United Nations Office on Drugs and Crime in the last decade and case reports bring attention to its high potency effects and its severe toxicity, including fatalities. Moreover, synthetic cannabinoids are usually entirely metabolized and metabolic pathways for many new generation synthetic cannabinoids are still unknown. In this study, the metabolism of five third generation synthetic cannabinoids were evaluated using zebrafish (Danio rerio) larvae as 24-hours in vivo model studied within 5 days after fertilization. The studied synthetic cannabinoids were MMB-CHMICA, ADB-CHMICA, ADB-CHMINACA, …
Metabolism of n-Butyl Benzyl Phthalate in the Female Wistar Rat. Identification of New Metabolites
1999
International audience; n-Butyl benzyl phthalate (BBP), a plasticizer used in polyvinylchloride (PVC) and other polymers, has been orally administered to female Wistar rats with four doses (150, 475, 780 and 1500 mg/kg body weight/day) for 3 consecutive days. Metabolites recovered in urines were analysed by gas chromatography±mass spectrometry (GC±MS) after 24, 48 and 72 hours. Six metabolites were identi®ed. Mono-n-butyl phthalate (MBuP) and mono-n-benzyl phthalate (MBeP) represented respectively 29± 34% and 7±12 % of the total recovered metabolites. Hippuric acid, the main metabolite of benzoic acid, represented the second major metabolite (51±56%). Phthalic acid, benzoic acid and an o-ox…
Applying Support Vector Machines for Gene Ontology based gene function prediction.
2004
Abstract Background The current progress in sequencing projects calls for rapid, reliable and accurate function assignments of gene products. A variety of methods has been designed to annotate sequences on a large scale. However, these methods can either only be applied for specific subsets, or their results are not formalised, or they do not provide precise confidence estimates for their predictions. Results We have developed a large-scale annotation system that tackles all of these shortcomings. In our approach, annotation was provided through Gene Ontology terms by applying multiple Support Vector Machines (SVM) for the classification of correct and false predictions. The general perform…
Sevoflurane Impairs Cerebral Blood Flow Autoregulation in Rats: Reversal by Nonselective Nitric Oxide Synthase Inhibition
2005
UNLABELLED In this study, we investigated the effects of 1.0 and 2.0 minimum alveolar anesthetic concentration (MAC) sevoflurane on cerebral blood flow (CBF) autoregulation before and after nonselective inhibition of nitric oxide (NO) synthase in rats. Rats were randomly assigned as follows: Group 1 (n = 8): 1.0 MAC sevoflurane; Groups 2 and 3 (n = 8 per group): 2.0 MAC sevoflurane. Assessment of autoregulation within a mean arterial blood pressure range of 140-60 mm Hg was performed by graded hemorrhage before and after administration of l-arginine methyl ester (l-NAME, 30 mg/kg IV, Groups 1 and 2) or during hypocapnia (Group 3). In 10 additional animals, brain tissue NO(2)(-) concentratio…