Search results for " messenger"
showing 10 items of 1295 documents
The nicotinic acetylcholine receptor agonist (±)-epibatidine increases FGF-2 mRNA and protein levels in the rat brain
2000
Abstract In a previous work, we showed that acute intermittent nicotine treatment up-regulates the level of fibroblast growth factor-2 (FGF-2) mRNA in brain regions of tel- and mesencephalon of rats suggesting that neuroprotective effect of (−)nicotine may, at least in part, involve an activation of the neuronal FGF-2 signalling. The present experiments were designed to extend the study on the nicotinic receptor mediated up-regulation of FGF-2 mRNA levels to the use of the potent nicotinic acetylcholine receptor (nAChR) agonist (±)-epibatidine. The (±)-epibatidine treatment led to a strong and long lasting up-regulation of FGF-2 mRNA expression in the cerebral cortex, in the hippocampal for…
Addition of NMDA-receptor antagonist MK801 during oxygen/glucose deprivation moderately attenuates the upregulation of glucose uptake after subsequen…
2011
During stroke the blood–brain barrier (BBB) is damaged which can result in vasogenic brain edema and inflammation. The reduced blood supply leads to decreased delivery of oxygen and glucose to affected areas of the brain. Oxygen and glucose deprivation (OGD) can cause upregulation of glucose uptake of brain endothelial cells. In this letter, we investigated the influence of MK801, a non-competitive inhibitor of the NMDA-receptor, on the regulation of the glucose uptake and of the main glucose transporters glut1 and sglt1 in murine BBB cell line cerebEND during OGD. mRNA expression of glut1 was upregulated 68.7- fold after 6 h OGD, which was significantly reduced by 10 μM MK801 to 28.9-fold.…
Acute exercise induced changes in rat skeletal muscle mRNAs and proteins regulating type IV collagen content
2001
This experiment tested the hypothesis that running-induced damage to rat skeletal muscle causes changes in synthesis and degradation of basement membrane type IV collagen and to proteins regulating its degradation. Samples from soleus muscle and red and white parts of quadriceps femoris muscle (MQF) were collected 6 h or 1, 2, 4, or 7 days after downhill running. Increased muscle β-glucuronidase activity indicated greater muscle damage in the red part of MQF than in the white part of MQF or soleus. In the red part of MQF, type IV collagen expression was upregulated at the pretranslational level and the protein concentration decreased, whereas matrix metalloproteinase-2 (MMP-2), a protein th…
Differential regulation of interleukin-6 expression in human fibroblasts by tumor necrosis factor-alpha and lymphotoxin.
1990
The treatment of human diploid fibroblasts with tumor necrosis factor (TNF)-alpha and with lymphotoxin (LT) is associated with induction of interleukin-6 (IL-6) transcripts with TNF-alpha being 10-fold more potent than LT. Here we report on the TNF-alpha/LT-induced signaling mechanisms responsible for the regulation of IL-6 gene expression in these cells. Run-on assays demonstrated that both TNF-alpha and LT increase IL-6 mRNA levels by transcriptional activation of this gene. Stability studies of IL-6 transcripts in fibroblasts showed that TNF-alpha delayed IL-6 mRNA decay but not LT. The induction of IL-6 transcripts by TNF-alpha and LT was not inhibited by the isoquinoline sulfonamide de…
Developmental expression of human cartilage matrix protein.
1994
Cartilage matrix protein (CMP) is a non-collagenous component of cartilage with a yet unknown function. In this study we used in situ hybridization to investigate the temporal and sptial distribution of CMP transcripts during human embryonic and early fetal development, and compared it to the pattern of expression observed for collagen types I, II, X, and decorin. The distribution of CMP and collagen type II transcripts followed a similar pattern in the embryonic bone anlage, the fetal growth plate, and the developing vertebral column. Expression was highest in the upper hypertrophic and lower proliferative zone, whereas calcified cartilage was negative throughout the different stages of bo…
Induction of gamma-globin gene transcription by hydroxycarbamide in primary erythroid cell cultures from Lepore patients.
2008
Increased expression of fetal haemoglobin (HbF) may ameliorate the clinical course of beta-thalassemia and sickle cell disease. Some pharmacological agents, such as hydroxycarbamide (HC), can increase fetal haemoglobin synthesis during adult life. Cellular selection and/or molecular mechanisms have been proposed to account for this increase. To explore the mechanism of action of HC we focused on homozygous Hb-Lepore patients that presented with high fetal haemoglobin levels and were good responders to HC treatment "in vivo". We performed primary erythroid cultures from peripheral blood of four homozygous Lepore patients. The increase in HBG (gamma-globin) transcription levels and HbF conten…
Histamine up-regulates phosphodiesterase 4 activity and reduces prostaglandin E2-inhibitory effects in human neutrophils.
2000
Objective: To investigate whether histamine produces up-regulation of phosphodiesterase (PDE) activity with functional consequences in human peripheral blood neutrophils.¶Methods: PDE activity was studied by a radioisotopic method following anion-exchange chromatography. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used for detection of mRNA transcripts of PDE4 subtypes. Cyclic AMP (cAMP) levels were measured by enzyme-immunoassay, and superoxide generation by cytochrome c reduction.¶Treatment: Neutrophils were incubated for 4 h with histamine (1 μM).¶Results: PDE4 was the only isoenzyme activity increased in treated neutrophils. Kinetic analysis showed a ∼1.5-fold increase …
Regulation of PTHrP and PTH/PTHrP receptor by extracellular Ca2+ concentration and hormones in the breast cancer cell line 8701-BC.
2000
AbstractIt was previously reported that 8701-BC breast tumour cells express the gene for parathyroid hormonerelated peptide (PTHrP) and PTH/PTHrP receptor (PTHrPR) and release immunoreactive PTHrP (iPTHrP) into the extracellular medium. Since the regulation of PTHrP and PTHrPR by breast cancer cells has been poorly investigated so far, we have chosen the 8701- BC cell line as a model system to investigate whether alterations in the extracellular Ca[2+] concentration ([Ca[2+]]) and treatment with some wellknown differentiation agents for breast cells, such as dimethyl sulfoxide, hydrocortisone, progesterone, prolactin, alltrans retinoic acid and transforming growth factorβ1 might (i) modulat…
Progestogens reduce thromboxane production by cultured human endothelial cells.
2011
Objectives Progestogens have been poorly studied concerning their roles in endothelial physiology. Prostanoids are vasoactive compounds, such as thromboxane A2, a potent vasoconstrictor, and prostacyclin, a vasodilator. We examined the effects of two progestogens used clinically, progesterone and medroxyprogesterone acetate, on thromboxane A2 production by cultured human umbilical vein endothelial cells (HUVEC) and investigated the role of progesterone receptors and the enzymes involved in production of thromboxane A2 and prostacyclin. Methods Cells were exposed to 1‐100 nmol/l of either progesterone or medroxyprogesterone acetate, and thromboxane A2 production was measured in culture mediu…
Vasoactive intestinal peptide stimulation of cyclic guanosine monophosphate formation: further evidence for a role of nitric oxide synthase and cytos…
1993
In the rat pineal gland vasoactive intestinal peptide (VIP) and beta-adrenergic agonists stimulate cyclic guanosine monophosphate (cGMP) formation and their action is amplified by alpha 1-adrenergic agonists. Since beta-adrenergic stimulation of cGMP is suggested to involve activation of nitric oxide (NO) synthase and NO-mediated activation of cytosolic guanylate cyclase (GC), we investigated the effects of the NO synthase inhibitor N-monomethyl-L-arginine (L-NMMA) and of the cytosolic GC inhibitor methylene blue (MB) on VIP receptor-stimulated cGMP formation. Both L-NMMA and MB depressed VIP-induced cGMP formation as well as alpha 1-adrenergic potentiation of VIP-stimulated cGMP formation …