Search results for "ligands"
showing 10 items of 721 documents
Regulation of noradrenergic coerulean neuronal firing mediated by 5-HT2 receptors: involvement of the prepositus hypoglossal nucleus.
1991
Abstract Previous studies have indicated a 5-HT2-mediated inhibitory influence on unit activity in the locus coeruleus. In the present work, attempts were made to determine which area(s) of the brain is (are) involved in this effect: (1) Microiontophoretic application of serotoninergic compounds (quipazine, ketanserin, RU 24969 (Roussel Uclaf), 8-hydroxy-2(di-n-propylamino) tetralin (8-OH-DPAT), metergoline, serotonin) in the locus coeruleus, did not alter the coerulean discharge. Local microinjection of quipazine or ketanserin in the area of the locus coeruleus, as well as in one of its major afferents, the prepositus hypoglossi, had no effect on the unit activity in the locus coeruleus. 1…
Progastrin Represses the Alternative Activation of Human Macrophages and Modulates Their Influence on Colon Cancer Epithelial Cells
2014
Macrophage infiltration is a negative prognostic factor for most cancers but gastrointestinal tumors seem to be an exception. The effect of macrophages on cancer progression depends on their phenotype, which may vary between M1 (pro-inflammatory, defensive) to M2 (tolerogenic, pro-tumoral). Gastrointestinal cancers often become an ectopic source of gastrins and macrophages present receptors for these peptides. The aim of the present study is to analyze whether gastrins can affect the pattern of macrophage infiltration in colorectal tumors. We have evaluated the relationship between gastrin expression and the pattern of macrophage infiltration in samples from colorectal cancer and the influe…
TLR7 and TLR8 ligands and antiphospholipid antibodies show synergistic effects on the induction of IL-1beta and caspase-1 in monocytes and dendritic …
2009
TLRs represent the first line of defense against invading pathogens in the innate immune system. Certain cytokines are important mediators and essentially necessary to assure an appropriately regulated immune response. Recent data gave initial evidence that IL-1beta is one of the most relevant members of these regulating cytokines. We investigated the induction of IL-1beta production in monocytes and pDCs stimulated with ligands for TLR7 and TLR8 and with antiphospholipid antibodies (aPL). Using human monocytes and pDCs for stimulation with specific TLR7 and TLR8 ligands such as resiquimod (R848) and single stranded RNA (RNA42) as well as with a human monoclonal aPL HL5B resulted in a speci…
Furosemide action on cerebellar GABA(A) receptors in alcohol-sensitive ANT rats.
1999
Furosemide increases the basal tert-[35S]butylbicyclophosphorothionate ([35S]TBPS) binding and reverses the inhibition of the binding by gamma-aminobutyric acid (GABA) in the cerebellar GABA(A) receptors containing the alpha6 and beta2/beta3 subunits. These effects are less pronounced in the alcohol-sensitive (ANT) than in the alcohol-insensitive (AT) rat line. The difference between the rat lines in the increase of basal [35S]TBPS binding was removed after a longer preincubation with ethylendiaminetetraacetic acid (EDTA) containing buffer, but long preincubation did not reduce the GABA content of the incubation fluid or remove the difference in GABA antagonism by furosemide. The GABA sensi…
Blunted furosemide action on cerebellar GABAA receptors in ANT rats selectively bred for high alcohol sensitivity.
1996
Furosemide specifically reverses the inhibition by gamma-aminobutyric acid (GABA) of t-[35S]-butylbicyclophosphorothionate ([35S]TBPS) binding and increases the basal [35S]TBPS binding to the cerebellar granule cell layer GABAA receptors. For the selectivity of furosemide, an interplay between GABAA receptor alpha 6 and beta 2 or beta 3 subunits is needed. We have now investigated the furosemide sensitivity of cerebellar [35S]TBPS binding in the alcohol-sensitive (ANT) rat line that harbors a pharmacologically critical point mutation in the alpha 6 subunit [alpha 6 (Q1000)], increasing benzodiazepine affinity of the normally insensitive alpha 6-containing receptors. ANT receptors were less …
Glucocorticoids as modulators of expression and activity of Antithrombin (At): potential clinical relevance.
2014
Abstract Introduction An inverse relationship has been reported between decreased postoperative Antithrombin (AT) plasmatic levels and the incidence of complications. We hypothesized that Nuclear Hormone Receptors could modulate the expression of SERPINC1 , encoding AT, through a Hormone Regulatory Element present in its promoter, and thus hormone analogs could be a pharmacological complement in surgical procedures to activate endogenous AT synthesis. Materials and Methods The expression of SERPINC1 was analyzed in HepG2 cells by quantitative RT-PCR and Western Blot. Two studies were conducted with (a) patients submitted to cardiac surgery with cardiopulmonary bypass receiving (n =17) or no…
Oxytocin Regulates Neurosteroid Modulation of GABAAReceptors in Supraoptic Nucleus around Parturition
2003
In this study, we investigate how neurosteroid sensitivity of GABAAreceptors (GABAARs) is regulated. We examined this issue in neurons of the supraoptic nucleus (SON) of the rat and found that, during parturition, the GABAARs become insensitive to the neurosteroid allopregnanolone attributable to a shift in the balance between the activities of endogenous Ser/Thr phosphatase and PKC. In particular, a constitutive endogenous tone of oxytocin within the SON after parturition suppressed neurosteroid sensitivity of GABAARs via activation of PKC. Vice versa before parturition, during late pregnancy, application of exogenous oxytocin brings the GABAARs from a neurosteroid-sensitive mode toward a …
The hematopoietic factor G-CSF is a neuronal ligand that counteracts programmed cell death and drives neurogenesis.
2005
G-CSF is a potent hematopoietic factor that enhances survival and drives differentiation of myeloid lineage cells, resulting in the generation of neutrophilic granulocytes. Here, we show that G-CSF passes the intact blood-brain barrier and reduces infarct volume in 2 different rat models of acute stroke. G-CSF displays strong anti-apoptotic activity in mature neurons and activates multiple cell survival pathways. Both G-CSF and its receptor are widely expressed by neurons in the CNS, and their expression is induced by ischemia, which suggests an autocrine protective signaling mechanism. Surprisingly, the G-CSF receptor was also expressed by adult neural stem cells, and G-CSF induced neurona…
Prevention of chemotherapy‐induced cachexia by ACVR2B ligand blocking has different effects on heart and skeletal muscle
2017
Background Toxicity of chemotherapy on skeletal muscles and the heart may significantly contribute to cancer cachexia, mortality, and decreased quality of life. Doxorubicin (DOX) is an effective cytostatic agent, which unfortunately has toxic effects on many healthy tissues. Blocking of activin receptor type IIB (ACVR2B) ligands is an often used strategy to prevent skeletal muscle loss, but its effects on the heart are relatively unknown. Methods The effects of DOX treatment with or without pre-treatment with soluble ACVR2B-Fc (sACVR2B-Fc) were investigated. The mice were randomly assigned into one of the three groups: (1) vehicle (PBS)-treated controls, (2) DOX-treated mice (DOX), and (3) …
A novel dimer of oxo-di(acetato)-bridged manganese(III) dimers complex of potential biological significance
2000
[EN] Assembly of the tetranuclear oxomanganese(III) acetato cluster [Mn4O2(O2CMe)(7)(phen)(2)](BF4) from the dinuclear oxo-di(acetato)bridged manganese(III) species [Mn2O(O2CMe)(2)(H2O)(2)(phen)(2)](BF4)(2) . 3H(2)O in aqueous/acetic acid MeOH solution occurs via the new 'dimer of dimers' Mn-III complex [Mn2O(O2CMe)(3)(H2O)(phen)(2)](BF4) . MeOH possesing an unprecedent [Mn-4(mu-O)(2)(mu-O2Me)(4) (mu-(OH2O2CMe)-O-...)(2)] core.