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Zuchner T, Schumer F, Berger-Hoffmann R, Müller K, Lukas M, Zeckert K, Marx J, Hennig H, Hoffmann R. Highly Sensitive Protein Detection Based on Lanthanide Chelates with Antenna Ligands Providing a Linear Range of Five Orders of Magnitude. Anal Chem 2009; 81:9449-53. [DOI: 10.1021/ac902175g] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Thole Zuchner
- Institute of Bioanalytical Chemistry, Center of Biotechnology and Biomedicine, Faculty of Chemistry and Mineralogy, Leipzig University, Deutscher Platz 5, 04103 Leipzig, Germany, XynTec Chemie GmbH Wolfen, ChemiePark Bitterfeld Andresenstrasse 1a, D-06766 Wolfen, Germany, and Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany
| | - Frank Schumer
- Institute of Bioanalytical Chemistry, Center of Biotechnology and Biomedicine, Faculty of Chemistry and Mineralogy, Leipzig University, Deutscher Platz 5, 04103 Leipzig, Germany, XynTec Chemie GmbH Wolfen, ChemiePark Bitterfeld Andresenstrasse 1a, D-06766 Wolfen, Germany, and Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany
| | - Renate Berger-Hoffmann
- Institute of Bioanalytical Chemistry, Center of Biotechnology and Biomedicine, Faculty of Chemistry and Mineralogy, Leipzig University, Deutscher Platz 5, 04103 Leipzig, Germany, XynTec Chemie GmbH Wolfen, ChemiePark Bitterfeld Andresenstrasse 1a, D-06766 Wolfen, Germany, and Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany
| | - Katrin Müller
- Institute of Bioanalytical Chemistry, Center of Biotechnology and Biomedicine, Faculty of Chemistry and Mineralogy, Leipzig University, Deutscher Platz 5, 04103 Leipzig, Germany, XynTec Chemie GmbH Wolfen, ChemiePark Bitterfeld Andresenstrasse 1a, D-06766 Wolfen, Germany, and Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany
| | - Mathias Lukas
- Institute of Bioanalytical Chemistry, Center of Biotechnology and Biomedicine, Faculty of Chemistry and Mineralogy, Leipzig University, Deutscher Platz 5, 04103 Leipzig, Germany, XynTec Chemie GmbH Wolfen, ChemiePark Bitterfeld Andresenstrasse 1a, D-06766 Wolfen, Germany, and Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany
| | - Kornelia Zeckert
- Institute of Bioanalytical Chemistry, Center of Biotechnology and Biomedicine, Faculty of Chemistry and Mineralogy, Leipzig University, Deutscher Platz 5, 04103 Leipzig, Germany, XynTec Chemie GmbH Wolfen, ChemiePark Bitterfeld Andresenstrasse 1a, D-06766 Wolfen, Germany, and Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany
| | - Jörg Marx
- Institute of Bioanalytical Chemistry, Center of Biotechnology and Biomedicine, Faculty of Chemistry and Mineralogy, Leipzig University, Deutscher Platz 5, 04103 Leipzig, Germany, XynTec Chemie GmbH Wolfen, ChemiePark Bitterfeld Andresenstrasse 1a, D-06766 Wolfen, Germany, and Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany
| | - Horst Hennig
- Institute of Bioanalytical Chemistry, Center of Biotechnology and Biomedicine, Faculty of Chemistry and Mineralogy, Leipzig University, Deutscher Platz 5, 04103 Leipzig, Germany, XynTec Chemie GmbH Wolfen, ChemiePark Bitterfeld Andresenstrasse 1a, D-06766 Wolfen, Germany, and Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany
| | - Ralf Hoffmann
- Institute of Bioanalytical Chemistry, Center of Biotechnology and Biomedicine, Faculty of Chemistry and Mineralogy, Leipzig University, Deutscher Platz 5, 04103 Leipzig, Germany, XynTec Chemie GmbH Wolfen, ChemiePark Bitterfeld Andresenstrasse 1a, D-06766 Wolfen, Germany, and Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany
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Rasouli M, Trischuk TC, Lehner R. Calmodulin antagonist W-7 inhibits de novo synthesis of cholesterol and suppresses secretion of de novo synthesized and preformed lipids from cultured hepatocytes. Biochim Biophys Acta Mol Cell Biol Lipids 2004; 1682:92-101. [PMID: 15158760 DOI: 10.1016/j.bbalip.2004.02.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2003] [Revised: 01/05/2004] [Accepted: 02/06/2004] [Indexed: 11/17/2022]
Abstract
The effects of a calmodulin antagonist W-7 were studied on the synthesis and secretion of lipids in primary rat hepatocytes and McArdle-RH7777 cells. In time course experiments, W-7 (20 microM) inhibited secretion of newly synthesized triacyl[(3)H]glycerol by 35%. When the cells were pre-treated overnight with W-7 (20 microM), followed by incubation with [(3)H]oleate, a significant decrease in the secretion of triacylglycerol (TG) and cholesteryl ester (CE) was observed. De novo synthesis of cholesterol from acetate or mevalonolactone was inhibited by W-7, but not glycerolipid synthesis from glycerol and oleic acid precursors. Concentration-response curves for the effects of overnight pre-incubation with W-7 followed labeling with [(3)H]glycerol and [(14)C]mevalonolactone revealed that: (1). the inhibitory effect of W-7 was concentration-dependent and appeared even at the lowest concentration examined (1 microM). W-7 at a concentration of 20 microM suppressed secretion of TG by 60% (P<or=0.002), phosphatidylcholine (PC) by 31% (P<or=0.05), CE by 59% (P<or=0.002) and cholesterol by 64% (P<or=0.002). (2). The incorporation of [(14)C]mevalonolactone into cellular cholesterol and CE was decreased significantly, while W-7 did not have any significant effect upon incorporation of [(3)H]glycerol into glycerolipids, except at the highest concentration examined (50 microM), where synthesis of both TG and PC was significantly suppressed. (3). While the percentage of secreted de novo synthesized glycerolipids and CE decreased proportionally with increasing concentration of W-7, the percentage of secreted newly made cholesterol remained unaffected at any concentration of W-7. In the absence of W-7, about 19% of newly formed cholesterol became esterified into CE, whereas W-7 increased cholesterol esterification in a concentration-dependent manner. (4) W-7 (20 microM) also suppressed the secretion of preformed cholesterol by 24% and CE by 55% but did not affect the recruitment of preformed cholesterol for esterification. About 6.5% of pre-labeled cholesterol and 20% of CE were directed to secretion, which was suppressed in the presence of W-7 by 17% (P<or=0.09) and 48% (P<or=0.001), respectively. These results suggest that, W-7 in the range of 1-20 microM inhibited de novo synthesis of cholesterol and the secretion of both de novo synthesized and preformed lipids.
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Affiliation(s)
- Mehdi Rasouli
- Departments of Pediatrics and Cell Biology, University of Alberta, 328 Heritage Medical Research Centre, Edmonton, AB, Canada T6G 2S2
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Abstract
Depression and anhedonia are two major symptoms of cocaine withdrawal in humans. Hence, pharmacological treatments effective in depression might also alleviate the symptoms of cocaine withdrawal. In the present study, the effects of acute and repeated administration of a tricyclic antidepressant, desmethylimipramine (DMI), were investigated in naive and cocaine-withdrawing rats. An animal model of cocaine withdrawal was used that employs the elevation in intracranial self-stimulation (ICSS) thresholds following the termination of prolonged periods of cocaine self-administration as a measure of an animal's "anhedonic" state. The influence of chronic DMI treatment on beta-adrenergic receptor binding and affinity was also correlated with the behavioral signs of cocaine withdrawal. Neither acute nor repeated DMI treatment influenced reward functions in rats that were not undergoing cocaine withdrawal. However, repeated DMI treatment significantly down-regulated beta-adrenergic receptors, and shortened the duration of the post-cocaine "anhedonia" (elevation in thresholds). Furthermore, the magnitude of the beta-adrenergic receptor down-regulation correlated significantly with the degree of effectiveness of DMI treatment in reversing the post-cocaine "anhedonia". However, chronic DMI treatment did reduce the amount of cocaine self-administered by the animals. The reversal of the post-cocaine anhedonia in this animal model of cocaine withdrawal by chronic DMI treatment demonstrates the potential usefulness of the model in identifying new pharmacotherapies for cocaine withdrawal. In addition, the results indicate that tricyclic antidepressants may be able to ameliorate some of the symptoms of cocaine withdrawal.
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Affiliation(s)
- A Markou
- Department of Neuropharmacology CVN-7, Scripps Research Institute, La Jolla, CA 92037
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Abstract
We have used quantitative autoradiography to localize in rat brain beta 1- and beta 2-adrenergic receptors. These receptors were labeled in vitro with 125I-labeled pindolol, an antagonist of beta-adrenergic receptors that binds nonselectively to both beta 1 and beta 2 subtypes. The selective inhibition of 125I-labeled pindolol binding with specific antagonists of beta 1 and beta 2 receptors allowed the visualization of beta-adrenergic receptor subtypes. High levels of beta 1 receptors were observed in the cingulate cortex, layers I and II of the cerebral cortex, the hippocampus, the Islands of Calleja, and the gelatinosus, mediodorsal, and ventral nuclei of the thalamus. High levels of beta 2 receptors were found in the molecular layer of the cerebellum, over pia mater, and in the central, paraventricular, and caudal lateral posterior thalamic nuclei. Approximately equal levels of beta 1 and beta 2 receptors occurred in the substantia nigra, the olfactory tubercle, layer IV of the cerebral cortex, the medial preoptic nucleus, and all nuclei of the medulla. The pronounced differences in the ratio of beta 1 to beta 2 receptors among brain regions suggests that the subtypes of beta-adrenergic receptors may play different roles in neuronal function.
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Snoek GT, Voorma HO, van Wijk R. Positive and negative cAMP-mediated control of tyrosine aminotransferase synthesis in Reuber H35 hepatoma cells. Eur J Biochem 1982; 123:217-22. [PMID: 6121706 DOI: 10.1111/j.1432-1033.1982.tb06519.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Induction of L-tyrosine:2-oxoglutarate aminotransferase (EC 2.6.1.5) by N6,O2'-dibutyryl-adenosine 3',5'-monophosphate (Bt2cAMP) in Reuber H35 hepatoma cells reaches a maximum value between 3-5 h after addition of Bt2cAMP and subsequently decreases in the continuous presence of Bt2cAMP. We have investigated the kinetics of the increase, i.e. induction, and the decrease, i.e. the repressed state, of the tyrosine-aminotransferase-synthesizing system under these conditions. Our experimental results are as follows. 1. The repressed state of the tyrosine-aminotransferase-synthesizing system is not caused by a decrease in the intracellular cAMP concentration. 2. The repressed state is inhibited by actinomycin D (while induction is not inhibited). 3. During the repressed state no effect of dexamethasone on tyrosine aminotransferase synthesis is found, while during induction Bt2cAMP and dexamethasone act synergistically. 4. Longer starvation of the cells in serum-free medium has no influence on the kinetics of the induction/repressed state curve. From these results we have concluded that the mechanism of the transition to the repressed state of the tyrosine-aminotransferase-synthesizing system is essentially different from the mechanism of deinduction which occurs after removal of the inducer. Moreover, the repressed state of the system is a phenomenon which is induced by Bt2cAMP separately from induction at a different level of protein synthesis.
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