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Van Cruchten S - - 2002
In this study the endometrial morphology of four dogs in oestrus and 10 dogs in late metoestrus was investigated with scanning electron microscopy. In early oestrus the cells were slightly convex with fairly long microvilli and cell boundaries that were apparent but situated on a deeper level than the cell ...
Crider Julie Y - - 2002
Non-pigmented ciliary epithelial (NPE) and trabecular meshwork (TM) cells are important in maintaining normal aqueous humor dynamics through the inflow and outflow routes, respectively. The current studies were undertaken to evaluate the ability of several beta-adrenergic receptor agonists to stimulate various antagonists to inhibit cAMP production in cultured immortalized human ...
Murakami-Murofushi Kimiko - - 2002
A novel bioactive lipid, cyclic phosphatidic acid (cPA), was isolated originally from myxoamoebae of a true slime mold, Physarum polycephalum, and has now been detected in a wide range of organisms from slime molds to humans. It has a cyclic phosphate at the sn-2 and sn-3 positions of the glycerol ...
Mundroff Michelle L - - 2002
Amperometry and cyclic voltammetry are two electrochemical techniques that enable the detection of electroactive neurotransmitters that are released from single cells. These techniques have provided the first chemical view of the events that occur during exocytosis. This unit describes the isolation of several cell types known for their exocytotic properties, ...
Fujita Takashi - - 2002
cAMP signaling, activated by extracellular stimuli such as parathyroid hormone, has cell type-specific effects important for cellular proliferation and differentiation in bone cells. Recent evidence of a second enzyme target for cAMP suggests divergent effects on extracellular-regulated kinase (ERK) activity depending on Epac/Rap1/B-Raf signaling. We investigated the molecular mechanism of ...
Satoh Akira - - 2002
Regulation of energy balance in photosystems in response to extremely-high-CO2 (40%) and low-CO2 (0.04%) stress was studied in extremely-high-CO2-tolerant green microalgae, Chlorococcum littorale and Chlorella sp. UK001. To investigate the energy input process, we assessed an F714/F685-ratio in a 77K fluorescence emission spectrum induced by 440-nm excitation in intact cells, ...
Manfredi Giovanni - - 2002
Levels of phosphorylated adenosine nucleotides, including the universal energy carrier adenosine 5(')-triphosphate (ATP) and its metabolites adenosine 5(')-diphosphate (ADP) and adenosine 5(')-monophosphate (AMP), define the energy state in living cells and are dependent mainly on mitochondrial function. In this article, we describe a method based on the luciferase-luciferin system used ...
Sakwe Amos M - - 2002
Preproparathyroid hormone (prepro-PTH) is one of the proteins abundantly synthesized by parathyroid chief cells; yet under normal growth conditions, little or no prepro-PTH can be detected in these cells. Although this may be attributed to effective cotranslational translocation and proteolytic processing, proteasome-mediated degradation of PTH precursors may be important in ...
Tsai Yan-Jyu - - 2002
The effects of saikosaponins (a, b(1), b(2), c, d), isolated from Bupleurum Radix, on the induction of differentiation in rat C6 glioma cells were studied. Saikosaponins a and d were shown to inhibit cell proliferation and alter cell morphology. In addition to cytostasis, the enzymatic activities of glutamine synthetase (GS) ...
Miller J M - - 2002
The insect fat body is a dynamic tissue involved in maintaining homeostasis. It functions not only in energy storage and intermediary metabolism but also in detoxification, communication and the immune response. Some of these functions are confined to distinct groups of fat body cells. In Drosophila melanogaster, discrete precursor-cell clusters ...
Zhang Bo - - 2002
We investigated the effects of inhibitors of cAMP-specific phosphodiesterase type IV (PDE IV) on cultured rat microglial cells. Microglial cells expressed mRNA encoding PDE IV. Rolipram and RO-20-1724, specific inhibitors of PDE IV, elevated the intracellular cAMP level much higher than the other types of PDE inhibitors. cAMP in astrocytes ...
Sitaramayya Ari - - 2002
Soluble guanylate cyclase catalyzes the formation of cyclic GMP using GTP as substrate. It is now well established that soluble guanylate cyclase is highly activated by nitric oxide, and that many of the effects of nitric oxide on various cells and tissues are mediated through increased production of cyclic GMP. ...
Faucheux N - - 2002
We have previously shown that the adenylyl cyclase, which produces cyclic AMP (cAMP) in Swiss 3T3 cells, is activated by their attachment to a cellulose substratum (Cuprophan, CU). This substratum adsorbs vitronectin poorly, prevents cell spreading and causes them to aggregate. By contrast, cells spread out on polystyrene and contain ...
Kumar Akhilesh - - 2002
Amoebae of the cellular slime mould Dictyostelium discoideum showed stimulated mitogenic activity when exposed to 200 microM isoproterenol, an activator of adenyl cyclase, for 30 min. Approximately 40% increase in cell proliferation was found at 48 h after isoproterenol treatment. A faster and larger plaque formation as well as higher ...
Morton David B. - - 2002
Eclosion hormone (EH) is a 62 amino acid neuropeptide that plays an integral role in triggering ecdysis behavior at the end of each molt. At least three populations of cells are thought to be targets for EH, each of which show an EH-stimulated increase in the intracellular messenger guanosine 3', ...
Grbovic Olivera - - 2002
8-Chloro-cyclic-adenosine-3',5'-monophosphate (8-Cl-cAMP), a site-selective synthetic cyclic adenosine 3',5'-monophosphate (cAMP) analog exhibits growth inhibition in a broad spectrum of human cancer lines. However, detailed studies on the effects exerted by cAMP analogs on cell-cycle kinetics have been lacking. We have examined and compared the effect of 8-Cl-cAMP on cell-cycle kinetics in ...
Xu Z - - 2001
AMP 579, an adenosine A(1)/A(2) receptor agonist, has a strong anti-infarct effect when administered just before reperfusion. Because oxidative stress has been proposed to contribute to myocardial reperfusion injury, we tested whether AMP 579 can reduce the production of reactive oxidant species (ROS) during reoxygenation in cultured chick embryonic cardiomyocytes. ...
Reeves Philip G. - - 2001
The Caco-2 cell model was used to study the efficiency of absorption and endogenous excretion of zinc (Zn) regulated by dietary Zn concentration. Cells were seeded onto high pore-density membranes and maintained in medium supplemented with 10% FBS. After confluence, cells were treated with 5 or 25 &mgr;mol Zn/L for ...
Sharma A - - 2001
The effects of a vasoactive intestinal peptide (VIP) receptor antagonist (VIPhyb) on human glioblastoma cells were characterized. Pituitary adenylate cyclase activating polypeptide (125I-PACAP-27) bound with high affinity to U87, U118, and U373 cells. Specific 125I-PACAP-27 binding to U87 cells was inhibited, with high affinity, by PACAP but not VIP or ...
Shozu M - - 2001
Fetal human osteoblast-like cells and the THP-1 cell line that differentiates into macrophage/osteoblast-like cells in the presence of Vitamin D3 and which possesses high aromatase activity, constitute a useful model with which to study the regulation of aromatase in bone. We showed that dexamethasone (DEX)-induced aromatase activity in the THP-1 ...
Bradley K K - - 2001
We examined the effects of purines and the pyrimidine UTP on cellular proliferation in the human astrocytoma cell line 1321N1. Treatment of cultured cells with 100 microM ATP or 2-chloroadenosine (2-CA) resulted in significant reductions in cell numbers after 2 days, whereas adenosine (ADO) exhibited a slower time course of ...
Waters C M - - 2001
There is presently significant interest in cellular responses to physical forces, and numerous devices have been developed to apply stretch to cultured cells. Many of the early devices were limited by the heterogeneity of deformation of cells in different locations and by the high degree of anisotropy at a particular ...
Lee J J - - 2001
Cells of Gordonia nitida LE31 grown on 3-methylpyridine degraded 3-ethylpyridine without a lag time and vice versa. Cyclic intermediates were not detected, but formic acid was identified as a metabolite. Degradation of levulinic acid was induced in cells grown on 3-methylpyridine and 3-ethylpyridine. Levulinic aldehyde dehydrogenase and formamidase activities were ...
Kanda N - - 2001
We studied the activities of 3',5'-adenosine-cyclic monophosphate (cAMP)- synthesizing adenylate cyclase (AC) and cAMP-hydrolyzing cyclic nucleotide phosphodiesterase (PDE) in phytohemagglutinin (PHA)- or anti-CD3 plus anti-CD28-stimulated human T cells, and examined their roles in interleukin-13 (IL-13) production. The AC inhibitor MDL 12,330A [cis-N-(2-phenylcyclopentyl)azacyclotridec-1-en-2-amine hydrochloride] completely blocked PHA- or anti-CD3/CD28-induced IL-13 production. ...
Dervieux T - - 2001
Thioguanine and mercaptopurine are prodrugs requiring conversion into thiopurine nucleotides to exert cytotoxicity. Thiopurine S-methyltransferase (TPMT), an enzyme subject to genetic polymorphism, catabolizes thiopurines into inactive methylated bases, but also produces methylthioguanine nucleotides and methylmercaptopurine nucleotides from thioguanine and mercaptopurine nucleotides, respectively. To study the effect of TPMT on activation ...
Weinman E J - - 2001
Na(+)/H(+) exchanger regulatory factor (NHERF), an essential protein cofactor in cAMP-mediated inhibition of Na(+)/H(+) exchange transporter 3 (NHE3), facilitates the formation of a signal complex of proteins that includes NHE3, NHERF, and ezrin. This model for NHE3 regulation was developed in fibroblasts and its applicability to epithelial cells remains to ...
Sutters M - - 2001
Polycystic kidney disease (PKD) is characterized by the abnormal proliferation of tubular epithelial cells. It was recently shown that the growth of PKD cyst-lining cells is stimulated by cyclic adenosine monophosphate (cAMP), whereas the growth of normal human kidney cortex cells is inhibited. We have examined the effects of overexpressing ...
Wiemelt A P - - 2001
Although 3',5'-cyclic AMP (cAMP) is known to regulate oligodendrocyte development in vitro, little is known about the identity of agonists that induce cAMP synthesis in oligodendroglia. To identify such agonists, we used a novel immunohistochemical method of visualizing cAMP within single cells to screen compounds that are known to activate ...
Kim S N - - 2001
8-Cl-cyclic adenosine monophosphate (8-Cl-cAMP) has been known to induce growth inhibition and differentiation in a variety of cancer cells by differential modulation of protein kinase A isozymes. To understand the anticancer activity of 8-Cl-cAMP further, we investigated the effect of 8-Cl-cAMP on apoptosis in human cancer cells. Most of the ...
Edwards M E - - 2001
Shear stress and strain lead to neurodegeneration in vivo during head injury, glaucoma, and certain repetitive motion disorders. In vitro, shear stress and strain have been shown to lead to cell injury in a number of models using neurons and neuron-like cells. In the present study we examined the relationship ...
Rekasi Z - - 2001
We evaluated the effects of GHRH antagonists on the proliferation of MiaPaCa-2 human pancreatic cancer cells and cAMP signaling in vitro. GHRH antagonists inhibited the proliferation of MiaPaCa-2 cells in vitro in a dose-dependent way and caused a significant elevation in cAMP production. In a superfusion system, short-term exposure of ...
Pavan B - - 2001
In human amnion-derived WISH cells [(3)H]estradiol-17beta binding sites are not detectable, but they become measurable in cells exposed to cAMP elevating agents such as forskolin or Ro 20-1724. In cells unexposed to these drugs, 17beta-estradiol stimulates prostaglandin (PG)E(2) release but exerts an evident inhibitory effect in cells exposed to Ro ...
Glavas N A - - 2001
Agents that increase intracellular cAMP inhibit the activation and function of T cells and can lead to cell death. Recently, it has been postulated that cAMP inhibits T cell function in large part by acting as a brake on the T cell receptor and costimulatory receptor pathways. Therefore, for full ...
Ginés S - - 2001
Chronic exposure of A(1) adenosine receptors (A(1)R) to A(1)R agonists leads to activation, phosphorylation, desensitization, and internalization to intracellular compartments of the receptor. Desensitization and internalization of A(1)R is modulated by adenosine deaminase (ADA), an enzyme that regulates the extracellular concentration of adenosine. ADA interacts with A(1)R on the cell ...
Hayes S A - - 2001
The GATA-like transcription factor gene serpent is necessary for embryonic fat-cell differentiation in Drosophila (Sam, S., Leise, W. and Hoshizaki, D. K. (1996) Mech. Dev. 60, 197-205) and has been proposed to function in a cell-fate choice between fat cell and somatic gonadal precursors (Moore, L. A., Broihier, H. T., ...
Franco L - - 2001
CD38 is a bifunctional ectoenzyme synthesizing from NAD(+) (ADP-ribosyl cyclase) and degrading (hydrolase) cyclic ADP-ribose (cADPR), a powerful universal calcium mobilizer from intracellular stores. Recently, hexameric connexin 43 (Cx43) hemichannels have been shown to release cytosolic NAD(+) from isolated murine fibroblasts (Bruzzone, S., Guida, L., Zocchi, E., Franco, L. and ...
Calvet J P - - 2001
Autosomal dominant polycystic kidney disease (ADPKD) is a major, inherited disorder that is characterized by the growth of large, fluid-filled cysts from the tubules and collecting ducts of affected kidneys, and by a number of extrarenal manifestations including liver and pancreatic cysts, hypertension, heart valve defects, and cerebral and aortic ...
Neidlinger-Wilke C - - 2001
Many types of cells, when grown on the surface of a cyclically stretched substrate, align away from the stretch direction. Although cell alignment has been described as an avoidance response to stretch, the specific deformation signal that causes a cell population to become aligned has not been identified. Planar surface ...
Bryan-Lluka L J - - 2001
The effects of short- and long-term exposure of cells to elevated cyclic adenosine monophosphate (c-AMP), using dibutyryl-c-AMP, 8-bromo-c-AMP, cholera toxin or forskolin, or cyclic guanosine monophosphate (c-GMP), using dibutyryl-c-GMP or 8-bromo-c-GMP, on the activity and expression of the noradrenaline transporter (NAT) were examined. Short- or long-term c-GMP elevation had no ...
Sugihara H - - 2001
BACKGROUND: Fat cells (stromal tissue cells), not only have the function of lipid metabolism, but produce various cytokines that exert an influence on other cell types through paracrine or endocrine mechanisms. OBJECTIVES: To elucidate possible roles of fat cells in the skin, we examined their effects on the biological behaviour ...
Powers J F - - 2001
Increase of intracellular cyclic adenosine monophosphate by the permeant cyclic adenosine monophosphate analog, 8-(4-chlorophenylthio)-adenosine 3':5'- cyclic monophosphate, is mitogenic for normal adult rat chromaffin cells. The mitogenic effect is blocked by the phosphatidylinositol 3-kinase inhibitor, LY294002, and is associated with accumulation of phosphorylated Akt and p70S6 kinase, suggesting that cyclic ...
Angelucci C - - 2001
We investigated the effect of placenta growth factor-1 (P1GF-1) on cell growth and on the release of nitric oxide (NO), cyclic AMP (cAMP) and cyclic GMP (cGMP) in human malignant epithelial cells. A noteworthy increase in proliferation was induced in choriocarcinoma cells (BeWo) by P1GF-1 treatment, while breast cancer cells ...
Morimoto C - - 2001
Norepinephrine induced lipolysis in rat fat cells, in vitro, in a time- and concentration-dependent manner, without concomitantly increasing hormone-sensitive lipase (HSL) activity. It also induced, time and concentration dependently, HSL translocation from the cytosol to the lipid droplets in fat cells. Isoproterenol, forskolin, dibutyryl cyclic AMP, and theophylline also induced ...
Boterberg T - - 2001
Invasion of carcinoma cells is the result of a disequilibrium between invasion promoter and invasion suppressor gene products (1). The E-cadherin/catenin complex is the most potent invasion suppressor at the cell membrane of epithelioid cells (2).This complex consists of E-cadherin, a transmembrane glycoprotein of 120 kDa, which is linked to ...
Qi A D - - 2001
1. The human P2Y(11) (hP2Y(11)) receptor was stably expressed in two cell lines, 1321N1 human astrocytoma cells (1321N1-hP2Y(11)) and Chinese hamster ovary cells (CHO-hP2Y(11)), and its coupling to phospholipase C and adenylyl cyclase was assessed. 2. In 1321N1-hP2Y(11) cells, ATP promoted inositol phosphate (IP) accumulation with low microM potency (EC(50)=8.5+/-0.1 ...
El-Remessy A E - - 2000
PURPOSE: To determine the mechanism of cyclic AMP (cAMP) regulation of the interphotoreceptor retinoid-binding protein (IRBP) gene in retinoblastoma cells. METHODS: WERI-Rb1 cells pretreated with laminin or grown on poly-D-lysine-coated substratum for three days were treated with forskolin/3-isobutyl-1-methylxanthin (IBMX) or with dimethyl sulfoxide (DMSO). During a time course of 96 ...
Conigrave A D - - 2000
Extracellular ATP suppressed the growth of HL-60 leukemia cells and induced their differentiation as revealed by N-formyl-methionyl-leucyl-phenylalanine-induced beta-glucuronidase release. ATP degraded to ADP, AMP, and adenosine, and the effect of ATP on cell growth was mimicked by these metabolites added to the cultures. The stable analog alpha,beta-methylene ATP, however, had ...
Slotkin T A - - 2000
A variety of cancer cell lines, including MDA-MB-231 human breast cancer cells, exhibit mitotic inhibition by cAMP. In earlier work, we found that the phosphodiesterase inhibitor, theophylline, reduced the number of cells and altered cellular morphology. In the current study, we evaluated the effects of theophylline on macromolecule synthesis and ...
Ohkubo S - - 2000
We previously demonstrated that extracellular adenine nucleotides induced cyclic AMP elevation through local adenosine production at the membrane surface and subsequent activation of adenosine A(2A) receptors in NG108-15 cells. Furthermore, the adenosine formation was found to be mediated by an ecto-enzyme distinct from the ecto-5'-nucleotidase (CD73). In this study, we ...
Ohkubo S - - 2000
We previously demonstrated that extracellular adenine nucleotides induced cyclic AMP elevation in NG108-15 cells. This response was resistant to adenosine deaminase (ADA) and the ecto-5'-nucleotidase (CD73) inhibitor alpha,beta-methylene ADP (alpha,beta-MeADP), but was inhibited by both P1- and P2-receptor antagonists. In the present study, we investigated the relationship between adenine nucleotide-induced ...
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