Search results for "Tissue distribution"
showing 10 items of 240 documents
Human cationic amino acid transporter hCAT-3 is preferentially expressed in peripheral tissues.
2001
At least five distinct carrier proteins form the family of mammalian cationic amino acid transporters (CATs). We have cloned a cDNA containing the complete coding region of human CAT-3. hCAT-3 is glycosylated and localized to the plasma membrane. Transport studies in Xenopus laevis oocytes revealed that hCAT-3 is selective for cationic L-amino acids and exhibits a maximal transport activity similar to other CAT proteins. The apparent substrate affinity and sensitivity to trans-stimulation of hCAT-3 resembles most closely hCAT-2B. This is in contrast to rat and murine CAT-3 proteins that have been reported to display a very low activity and to be inhibited by neutral and anionic L-amino acid…
A novel serine/threonine kinase gene, STK33 , on human chromosome 11p15.3
2001
Human chromosomal region 11p15 is known to be associated with several diseases including predispositions to develop various tumor types. In search of candidate genes, a novel human kinase gene is described, STK33, which codes for a serine/threonine protein kinase. The gene was discovered by comparative genome analysis of human chromosome 11p15.3 and its orthologous region on distal mouse chromosome 7. Human STK33 gene contains 12 exons as has been determined by the comparison to the full-length transcript amplified from human uterus RNA. Transcripts are found in a variety of tissues in at least two alternatively spliced forms as revealed by reverse transcriptase-polymerase chain reaction, c…
Inhibition of cancer growth by resveratrol is related to its low bioavailability.
2002
The relationship between resveratrol (RES) bioavalability and its effect on tumor growth was investigated. Tissue levels of RES were studied after i.v. and oral administration of trans-resveratrol (t-RES) to rabbits, rats, and mice. Half-life of RES in plasma, after i.v. administration of 20 mg t-RES/kg b.wt., was very short (e.g., 14.4 min in rabbits). The highest concentration of RES in plasma, either after i.v. or oral administration (e.g., 2.6 +/- 1.0 microM in mice 2.5 min after receiving 20 mg t-RES/kg orally), was reached within the first 5 min in all animals studied. Extravascular levels (brain, lung, liver, and kidney) of RES, which paralleled those in plasma, were always1 nmol/g f…
Fate of Linear and Branched Polyether-Lipids In Vivo in Comparison to Their Liposomal Formulations by 18F-Radiolabeling and Positron Emission Tomogra…
2015
In this study, linear poly(ethylene glycol) (PEG) and novel linear-hyperbranched, amphiphilic polyglycerol (hbPG) polymers with cholesterol (Ch) as a lipid anchor moiety were radiolabeled with fluorine-18 via copper-catalyzed click chemistry. In vivo investigations via positron emission tomography (PET) and ex vivo biodistribution in mice were conducted. A systematic comparison to the liposomal formulations with and without the polymers with respect to their initial pharmacokinetic properties during the first hour was carried out, revealing remarkable differences. Additionally, cholesterol was directly labeled with fluorine-18 and examined likewise. Both polymers, Ch-PEG27-CH2-triazole-TEG-…
Ex vivo and in vivo evaluation of [18F]PR04.MZ in rodents: a selective dopamine transporter imaging agent.
2009
N-4-Fluorobut-2-yn-1-yl-2beta-carbomethoxy-3beta-phenyltropane (PR04.MZ) has been developed as dopamine transporter (DAT) ligand for molecular imaging. It contains a terminally fluorinated, conformationally constrained nitrogen substituent that is well suited for the introduction of fluorine-18. The present report describes the pharmacological characterisation of [18F]PR04.MZ. The ligand shows an IC50 value of 2 nM against human DAT, whereas the IC50 value against human serotonin transporter and human noradrenalin transporter are lower (110 nM and 22 nM, respectively). Furthermore, its ex vivo organ distribution, its binding profile in the rat brain and reversibility of binding were examine…
In vivo biodistribution of amino-functionalized ceria nanoparticles in rats using positron emission tomography.
2012
A variety of nanoparticles have been proposed for several biomedical applications. To gauge the therapeutic potential of these nanoparticles, in vivo biodistribution is essential and mandatory. In the present study, ceria nanoparticles (5 nm average particle size) were labeled with F-18 to study their in vivo biodistribution in rats by positron emission tomography (PET). The F-18 isotope was anchored by reaction of N-succinimidyl 4-[F-18]fluorobenzoate (F-18-SFB) with a modified nanoparticle surface obtained by silylation with 3-aminopropylsilyl. Radiolabeled ceria nanoparticles accumulated mainly in lungs, spleen, and liver. Metabolic products of the radiolabeled nanoparticulate material w…
Expression and compartmentalisation of the glycolytic enzymes GAPDH and pyruvate kinase in boar spermatogenesis
2008
Boar spermatozoa contain isoforms of both glyceraldehyde 3-phosphate dehydrogenase (GAPDH, EC 1.2.1.12) and pyruvate kinase (PK, EC 2.7.1.40). The sperm-specific forms, GAPDH-S and PK-S, are tightly bound to cell structures. By immunofluorescence microscopy GAPDH-S and PK-S were localised in the principal piece of the boar sperm flagellum as well as in the acrosomal region of the sperm head and at the head–midpiece junction. The midpiece of the flagellum, however, contains isoforms of GAPDH and PK that were only recognised by antibodies against somatic GAPDH and PK, respectively, but not by the antibodies against GAPDH-S and PK-S. In sections of boar testis, GAPDH-S and PK-S were first dete…
Extensive characterization of the human DDAH1 transgenic mice
2009
Abstract Purpose of the research Overexpression of the human dimethylarginine dimethylaminohydrolase type 1 (hDDAH1) gene was reported to have beneficial cardiovascular effects in mice. To date, it is unclear whether these effects are related to enhanced metabolic clearance of asymmetric dimethylarginine (ADMA) and l - N G -mono-methyl- l -arginine ( l -NMMA) or increased DDAH1 expression and activity in cardiovascular tissues of hDDAH1 transgenic mice. Principal results DDAH activity (DDAH1 + DDAH2) was found to be markedly increased in aortic and heart tissues but unaltered in liver and kidney tissues of hDDAH1 transgenic as compared to wild-type (WT) mice. In WT mice, DDAH activity was m…
Distribution patterns in glycoconjugate expression during the development of the rat palate.
1994
The distribution of complex carbohydrate structures during the embryonic development of the rat palate was analysed by examining lectin-binding patterns in serial paraffin and cryostat sections. With few exceptions, the binding patterns showed a general increase in lectin receptors in the more developed stages of palatogenesis. High mannose oligosaccharides were especially amplified during development. Terminal fucose molecules were not expressed. In contrast, terminal sialic acid molecules were ubiquitously distributed in epithelial and mesenchymal tissues. Non-sialylated terminal N-acetylglucosamine was specifically restricted to evolving bone matrix. Before palatal fusion, quantitative b…
Expression of the rat connexin 39 (rCx39) gene in myoblasts and myotubes in developing and regenerating skeletal muscles: an in situ hybridization st…
2005
We report a detailed analysis of the expression pattern of the recently identified rat connexin gene, named rat connexin 39 (rCx39), both during embryonic development and in adult life. Qualitative and quantitative reverse transcription/polymerase chain reaction analysis showed intense expression of rCx39 restricted to differentiating skeletal muscles, with a peak of expression detected at 18 days of embryonic life, followed by a rapid decline to undetectable levels within the first week of postnatal life. A combination of the in situ hybridization technique for the detection of rCx39 mRNA and immunohistochemistry for myogenin, a myoblast-specific marker, allowed us to establish that the mR…