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Orlandi R - - 1997
To determine whether p185HER2 overexpression per se triggers p185HER2 cellular signaling or whether an extracellular signal is required, we transfected PC12 cells with the human erbB-2 proto-oncogene, and established a cell line that overexpresses p185HER2. PC12-HER2 cells, maintained in suspension culture or plated on a collagen layer, showed the same ...
Sato K - - 1997
Exogenous sphingosine 1-phosphate (S1P), like lysophosphatidic acid (LPA), induced neurite retraction or cell rounding in differentiated PC12 cells. The lysosphingolipid-induced shape change was detected at as low as 1 nM; however, a significant accumulation of intracellular S1P was not detected until 1 microM S1P was applied. Moreover, although exogenous sphingosine ...
Elwan M A - - 1997
The present study investigated the presence, possible synthesis and release of catecholamines (CA) by human amniotic epithelial cells (HAEC) using HPLC with electrochemical detection. The presence of CA was indicated by the detection of norepinephrine (NE), dopamine (DA) and its metabolite 3,4-dihydroxyphenylacetic acid (DOPAC) in extracts of cultured HAEC. Incubation ...
Hatayama T - - 1997
Rat pheochromocytoma PC12 cells differentiate into nonreplicating neuronal cells with neurite extensions in response to nerve growth factor (NGF). To gain better understanding of the regulation of stress responses in neuronal cells, we examined the induction of HSP70, HSP70 mRNA, and heat shock factor 1 (HSF1) DNA-binding activity following treatment ...
Fayad W - - 1997
Both pancreatic beta cells (insulin-secreting cells) and neuronal cells express functional receptors for nerve growth factor. However, while the effect of nerve growth factor on neuronal differentiation is well known, its role on pancreatic beta cells is not established. It has been demonstrated that in PC12 cells, a well characterized ...
Chang J Y - - 1997
Two novel populations of spontaneous PC12 cell mutants resistant to a toxic concentration of 25-OH-cholesterol (5 microg/ml, 12.5 microM) were isolated and designated as R25R and F25R based on cell morphology. R25R consisted of round cells that were morphologically similar to the parent PC12 cells, and responded to nerve growth ...
Shin J S - - 1997
The effects of noscapine, a phthalide isoquinoline alkaloid, on dopamine biosynthesis and tyrosine hydroxylase (TH) activity in PC12 cells were investigated. Noscapine showed 74.6% inhibition on dopamine content in PC12 cells at a concentration of 20 muM. IC(50) of noscapine was 6.8 muM. TH activity was inhibited by the treatment ...
Bayerl C - - 1997
OBJECTIVE: To study the immunoneurocrine network in inflammatory dermatoses, we investigated histochemically acute UV and acute contact dermatitis. METHODS: Antibodies were applied to frozen and paraffin specimens of human skin after irradiation (n = 10), to positive patch tests (n = 10) and controls (n = 10) against: HSP 70, ...
Stefanis L - - 1997
Rat pheochromocytoma (PC12) cells and sympathetic neurons undergo apoptotic cell death upon withdrawal of trophic support. We have shown previously that selective cysteine aspartase (caspase) inhibitors protect PC12 cells and sympathetic neurons from such death, and that the caspase Nedd-2 is required for this type of death to occur. We ...
Chang J Y - - 1997
The effects of cholesterol oxides on regular and neuronal PC12 cells were examined. Among the cholesterol oxides tested, 7-beta-, 22(R)- and 25-OH-cholesterol were very toxic to regular PC12 cells such that approximately 80% of cells were killed after a 3 day incubation with 20 micrograms/ml (50 microM) of these agents. ...
Koenigsberger C - - 1997
Previous observations from several groups suggest that acetylcholinesterase (AChE) may have a role in neural morphogenesis, but not solely by virtue of its ability to hydrolyze acetylcholine. We tested the possibility that AChE influences neurite outgrowth in nonenzymatic ways. With this aim, antisense oligonucleotides were used to decrease AChE levels ...
Güzey M - - 1997
A group of deltanoids has been used for studying the inhibition of cell growth and proliferation in two small cell lung carcinoma (SCLC) in vitro. The biologically active deltanoid, 1,25 dihydroxyvitamin D3 (1,25 (OH)2D3), has functions beyond its classical roles of stimulating calcium transport and serum calcium. It also causes ...
Wang Y - - 1997
The purpose of this study is to examine if microencapsulated PC12 cells may provide long term effects to the hemiparkinsonian rats. A modified technique was used to encapsulate PC12 cells into gelled microspheres. We found that the PC12 cells can survive in the modified microcapsules in vitro. Most of the ...
Roth J A - - 1997
Melatonin has previously been reported to influence cell differentiation and growth in a number of cell culture systems in vitro. In this paper, we describe the effects of high pharmacological and low physiological concentrations of melatonin on cell growth in rat pheochromocytoma cells (PC12 cells). Melatonin produced a biphasic response ...
Saura J - - 1997
Etoposide, a topoisomerase II inhibitor used in cancer therapy, has been shown to induce apoptosis in vitro in a variety of cell types. In the present study, we have characterized the effects of etoposide on undifferentiated rat pheochromocytoma PC12 cells. Etoposide killed PC12 cells in a time- and concentration-dependent manner. ...
Katoh S - - 1997
The rat pheochromocytoma cell line PC12 is useful for studying neuronal cell differentiation since this cell line differentiates into neuron-like cells in response to nerve growth factor (NGF). We demonstrated that PC12h cells, a subclone of PC12 cells, died under hyperoxia (50% O2). This cell death did not occur in ...
Qian Y - - 1997
We previously reported that copper efflux from C6 rat glioma cells was blocked by a brief exposure to sulfhydryl reagents p-chloromercuribenzoate (PCMB) and iodoacetamide as well as dicyclohexylcarbodiimide, suggesting the possible involvement of a Cu-transporting ATPase in the efflux mechanism. In this report, we show that copper efflux from PC12 ...
Marchetti D - - 1997
Heparanase is an endo-beta-D-glucuronidase whose enzymatic targets are the glycosaminoglycan chains of heparan sulfate proteoglycans. Elevated levels of heparanase are associated with the metastatic potential of melanoma cells. Treatment of murine and human melanoma cells with the prototypic neurotrophin nerve growth factor (NGF) increases the production of heparanase by melanoma ...
Clark R A - - 1997
Chemical analysis of single cells is an area of great interest in the biological sciences. Single-cell systems are being utilized as a model to understand in vivo processes better. One method that is moving to the forefront in cellular analysis is electrochemistry. Owing to their rapid response time and small ...
Corey J M - - 1997
The B104 neuroblastoma cell line was investigated for use as an assay for predicting the patterning of primary neurons. B104 cells were grown on four uniform substrates with the result that the cells preferred, in descending order, poly-D-lysine (PDL), phenyltrichlorosilane (PTCS), coverslip glass, and silicon dioxide coated coverslips. B104 cells ...
Ray P - - 1997
Stimulus-induced acetylcholine (ACh) exocytosis from presynaptic nerve terminals involves two important steps: fusion of ACh loaded vesicles at presynaptic release sites, followed by release into the synaptic cleft. We studied the role of the putative vesicle fusion protein SNAP-25 in this process. The nerve growth factor-differentiated PC12 cell line was ...
Berse B - - 1997
Modulation of mRNA expression of choline acetyltransferase (ChAT) and the vesicular acetylcholine transporter (VAChT) by the glucocorticoid dexamethasone and by retinoic acid was examined in two neuronal cell lines: basal forebrain-derived SN56 and pheochromocytoma PC12. Dexamethasone up-regulated ChAT and VAChT in SN56 cells, while it had inhibitory effects on these ...
Kojima T - - 1997
The kinetics of type I procollagen synthesis in a human osteosarcoma cell line, MG 63, were investigated after treatment with 1,25-dihydroxyvitamin D3 (1,25-(OH)2 D3), a hormonal inducer of phenotypic differentiation. Pulse label and chase experiments demonstrated greatly enhanced production and more rapid reduction of intracellular procollagen molecules in the 1,25-(OH)2 ...
Sherwood N T - - 1997
Trk receptor activation by neurotrophins is often considered to have a defined set of actions on target neurons, including supporting neuronal survival, inducing morphological differentiation, and regulating a host of target genes that specify neuronal phenotype. It is not known if all such regulatory effects are obligatory, or if some ...
Cross H S - - 1997
1Alpha,25-dihydroxyvitamin D3 (1alpha,25(OH)2D3) and its synthetic analogues exhibit structure-related variations in their growth inhibitory actions in human colon adenocarcinoma-derived Caco-2 cells. Because this might be caused by differences in resistance against metabolic degradation, we used high performance liquid chromatography (HPLC) analysis to investigate pathways of vitamin D metabolism in two ...
Gonzalez B J - - 1997
High concentrations of pituitary adenylate cyclase-activating polypeptide (PACAP) and its receptors have been detected in the rat cerebellum during ontogenesis. In particular, PACAP receptors are actively expressed in immature granule cells, suggesting that PACAP may act as a neurotrophic factor in the developing rat cerebellum. In the present study, we ...
Martínez M E - - 1997
Parathyroid hormone-related protein (PTHrP) is synthesized by osteoblasts, although its local role in bone is not completely understood. The C-terminal (107-111) region of PTHrP seems to be a potent inhibitor of osteoblastic bone resorption. We studied the effect of this PTHrP domain on the proliferation and synthesis of osteoblastic markers ...
Lelkes P I - - 1997
The aim of this study was to test the versatility of a new basal cell culture medium, GTSF-2. In addition to traditional growth-factors, GTSF-2 contains a blend of three sugars (glucose, galactose, and fructose) at their physiological levels. For these studies, we isolated normal endothelial cells from human, bovine, and ...
Weeks B S - - 1997
Here we treat neuronal cells with AIDS-Kaposi's sarcoma cell conditioned medium (A-KSCM) in order to determine if AIDS-Kaposi's sarcoma (A-KS) cells secrete neurotrophic factors. PC12 and NG108-15 cells were differentiated and allowed to form neuronal processes. Under these conditions and in the presence of A-KSCM, PC12 cells exhibited more than ...
Kawai Y - - 1997
It has been reported that cultured PC12 cells can be used as a model for studying mechanisms of O2 sensitivity, previously examined in peripheral chemoreceptors and some neurons. This study compared the hypoxic depression of K+ currents in two PC12 variants, before and after differentiation into neurone-like cells induced by ...
Ihara Y - - 1997
beta-1,4-N-Acetylglucosaminyltransferase III (GnT-III: EC 2.4.1.144) is a pivotal glycosyltransferase which participates in branch formation by catalysis of the synthesis of a bisecting GlcNAc structure in N-glycans. These structures are thought to be one of the unique features of the N-glycans of neural tissues. To examine the intracellullar role of GnT-III ...
Spilker C - - 1997
Wild-type neuronal calcium-binding protein VILIP (visinin-like protein), and a myristoylation mutant of VILIP which lacks the consensus sequence for N-terminal myristoylation, have been stably transfected in PC12 cells. Immunocytochemical studies of VILIP-transfected PC12 cells have revealed the wild-type VILIP is strongly concentrated at the cell membrane, particularly at cell-cell contact ...
Hossain M M - - 1997
Our previous in vivo and in vitro studies showed that 5-azacytidine (5Az), a cytidine analog, induced apoptosis in developing neuronal cells in mice. To develop a system in which the precise molecular mechanism of 5Az-induced apoptosis in developing neuronal cells could be elucidated, we carried out the present study with ...
Chen Y - - 1997
Nerve growth factor (NGF) is expressed by rat round spermatids and is thought to participate in the paracrine regulation of spermatogenesis. In order to elucidate the role of NGF in the rat testis, we further characterized the NGF immunoreactive protein secreted by round spermatids and examined the effect of NGF ...
Jiang H - - 1997
Human p140(trk) and p75(NGFR) were transfected separately into 3T3 cells. Nerve growth factor stimulates calcium uptake into both transfectants but not into untransfected 3T3 cells. p140(trk) cells were stimulated maximally by 25 ng/ml; 100 ng/ml was submaximal for p75(NGFR) cells. K-252a inhibits the effect of NGF on p140(trk) cells but ...
Graham M E - - 1997
The Ca2+/phospholipid/cytoskeletal-binding protein annexin II has been proposed to play an important role in Ca(2+)-dependent exocytosis; however, the evidence for this role is inconclusive. More direct evidence obtained by manipulating annexin II levels in cells is still required. We have attempted to do this by generating stably transfected PC12 cell ...
Lamoureux P - - 1997
Recent work has suggested that rac1 and other members of the rho family of small GTP-binding proteins play an important role in the formation of neural processes. We have explored the mechanism of this effect by comparing the spontaneous, growth cone-mediated growth and experimental tension-induced growth of axons in normal ...
Staal A A Department of Internal Medicine III, Erasmus University Medical School, Rotterdam, The - - 1997
A direct relationship between vitamin D receptor (VDR) level and target cell responsiveness to 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) has been shown in osteoblast-like cell lines. However, we previously found an inverse relationship between the TGF beta-induced VDR up-regulation and subsequent 1,25-(OH)2D3-induced biological responses. A clear inhibition of the 1,25-(OH)2D3-induced stimulation of ...
Cosgaya J M - - 1997
Conditioned medium from PC12 cells incubated with retinoic acid (RA) increases [3H]thymidine incorporation in normal rat kidney (NRK) fibroblasts and 3D9 epithelial cells. The medium also causes anchorage-independent growth of NRK cells, which is strongly potentiated either in the presence of EGF or after activation of latent forms of transforming ...
Venihaki M - - 1997
The adrenal medulla of several species and some human pheochromocytomas contain CRH. The first aim of the present work was to find out whether normal rat adrenal chromaffin cells and the PC12 rat pheochromocytoma cell line produce CRH in vitro and what regulates its production. CRH was measured and characterized ...
Lindenboim L - - 1997
1. The rat pheochromocytoma PC12 cell line has been a commonly used model for studies of neuronal development, function, and death. Thus the ability to transfect PC12 cells in an efficient manner and to manipulate their gene expression would enhance the usefulness of these cells. 2. We demonstrate that EBV-based ...
Zhao B - - 1997
The cause of neuronal loss in Alzheimer disease is unknown. We investigated the effects on survival of PC12 cells expressing A692G, E693Q, and V717F mutant amyloid precursor proteins (APP). Differentiated cells expressing mutant APPs exhibited somal shrinkage, followed by cell detachment from the plates. Increased levels of oligonucleosome-sized DNA ladders ...
Nakamura Y - - 1997
To investigate the biochemical mechanism responsible for NO-induced neurotoxicity, the effect of sodium nitroprusside(SNP), a NO-generating agent, on PC12 cells was studied. The cell density was dose-dependently inhibited by SNP. Neuronally differentiated PC12 cells showed a higher resistance to SNP than the undifferentiated cells. The inhibitory effect was enhanced by ...
Muragaki Y - - 1997
Neurotrophins act through their cognate receptors to promote the differentiation and/or survival of neuronal progenitor cells, immature neurons, and other cells. Here, we examined the effects of nerve growth factor (NGF) and its cognate receptor (Trk or TrkA) on the survival of a common childhood brain tumor, i.e., medulloblastoma, a ...
Smith S L - - 1997
The role of haem in the neurotoxicity of artemisinin derivatives has been studied in vitro by examining neurite outgrowth measured by image analysis and cellular metabolism of the tetrazolium salt MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide) measured spectrophotometrically in the neuroblastoma cell line NB2a, and by examining binding of radiolabelled dihydroartemisinin to NB2a ...
Li R - - 1997
Gangliosides are believed to play a critical role in cellular differentiation. To test this concept, we determined the effect of inhibition of endogenous ganglioside synthesis upon neurite formation induced by retinoic acid in LAN-5 human neuroblastoma cells. Ganglioside synthesis and content of LAN-5 cells exposed for 6 days to 10 ...
Glassman R H - - 1997
v-Crk is a member of a class of SH2 and SH3-containing adaptor proteins that have been implicated in regulating the TrkA receptor tyrosine kinase and potentiating Nerve Growth Factor (NGF)-mediated neurite outgrowth in pheochromocytoma (PC12) cells (Hempstead et al, Mol. Cell Biol. 14: 1964 - 1971). Given the fact that ...
Chen G - - 1997
Recent advances in the development of microscale analytical techniques have allowed minute amounts of compounds of biological interest to be monitored in microenvironments. Microcolumn separation techniques, such as microcolumn liquid chromatography and capillary electrophoresis, provide a means of obtaining high-efficiency separations of analytes in picoliter to femtoliter volume samples. Voltammetric ...
Fulle S - - 1997
When grown for seven days in a medium containing nerve growth factor (100 ng/ml), 10% horse serum and 5% fetal bovine serum PC12 cells stopped dividing, extended neurites and assumed a neuronal phenotype. Withdrawal of nerve growth factor from these cells resulted in loss of neurites and apoptotic changes in ...
Yudoh K - - 1997
We investigated the role of the active form of vitamin D, 1,25-dihydroxyvitamin D3[1,25(OH)2D3], in promoting tumor cell invasiveness through the extracellular matrix, and showed that 1,25(OH)2D3-induced reduction of laminin production by the cells was correlated with the inhibitory effect of the hormone on tumor cell invasiveness. 1,25(OH)2D3 significantly inhibited invasiveness ...
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