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Missale C - - 1994
GH-3 is an established cell line which, for the production of both PRL and GH, may be related to the bipotential somatomammotroph from which both somatotroph and mammotroph cells derive. In the present study we first report that GH-3 cells express both the gp140trk and the gp75 components of the ...
Lustig R H - - 1994
Estrogen alters neurite outgrowth, neuritic spine development, and synaptogenesis in estrogen-responsive areas of the rat brain. However, examination of the specific effects of estrogen on neurons in vivo has been difficult. An in vitro model for the effects of estrogen on neurons was developed, using the PC12 rat pheochromocytoma cell ...
Naveilhan P - - 1994
Newborn rat brain astrocytes, cultured in a serum-free medium, were exposed for 30 min to two types of reactive oxygen species. Cells were either treated with the xanthine/xanthine oxidase (X/XOD) system, which generates both H2O2 and the O2.- radical, or to H2O2 alone. Both treatments induced a dose-dependent accumulation of ...
Sampath D - - 1994
Nerve growth factor (NGF) is a member of the neurotrophin family and is required for the survival and maintenance of peripheral sympathetic and sensory ganglia. In the CNS, NGF regulates cholinergic expression by basal forebrain cholinergic neurons. NGF also stimulates cellular resistance to oxidative stress in the PC12 cell line ...
Zanellato A - - 1994
The glioma cell line C6 was used to study the expression and growth-dependent regulation of the nerve growth factor (NGF) tyrosine kinase receptor gp140trk, which is the mature protein product of the trk proto-oncogene. Chemical cross-linking of 125I-NGF to C6 cells, followed by immunoprecipitation with polyclonal anti-NGF antibodies and separation ...
Froissard P - - 1994
In order to investigate the biochemical mechanisms responsible for glutamate-induced cell death, we have tested the effect of this excitatory amino acid on the growth and survival of several cell lines of neural origin. Most of the cell lines studied were insensitive to glutamate, but we observed in PC12 cells ...
Rogers M V - - 1994
We show here that a protein tyrosine phosphatase inhibitor, sodium orthovanadate, induces rat pheochromocytoma cells to express neurites, a prominent morphological marker of neuronal phenotype. Vanadate-induced differentiation and neurite outgrowth in pheochromocytoma cells was not as extensive as that induced by the positive control employed, nerve growth factor. However, neurite ...
Zhou J - - 1994
The result of nerve growth factor (NGF) actions depends upon the cells in which it signals. To define how signaling is influenced by cellular context, it would be useful to examine cells committed to different fates or cells of a single type at different developmental stages. Interest in NGF actions ...
Morimoto M - - 1994
We investigated the effects of nerve growth factor (NGF) and glucocorticoid on the differentiation of rat chromaffin cells during development (postnatal day 0, 5, 10, 15, 25) in vitro, by evaluating four parameters of cytological alterations; the percentage of process-bearing cells, the number of primary processes, the number of branches ...
Leung S - - 1994
PC12 cells possess a bumetanide-sensitive Na/K/2Cl cotransport system similar to that found in other cell types. Between 10-15% of the total 86Rb influx in these cells is mediated by this pathway under normal conditions. The cotransporter has affinities of 16.5 mM for Nao and 0.7 mM for Ko, is absolutely ...
Aebischer P - - 1994
Cross-species neural grafting of cell lines immunoisolated by a permselective polymer membrane represents a promising source of neuroactive molecules for the treatment of neurodegenerative diseases. Utilization of a cell line of xenogeneic origin is advantageous since the transplanted cells will be rejected by the host immune system in case of ...
Marom M - - 1994
1. The relationships among the mevalonic acid (MVA) forming enzyme, 3-hydroxy-3-methylglutaryl coenzyme A (CoA) reductase, cell growth and differentiation, and the cytotoxic effects of the reductase inhibitor lovastatin were studied in PC-12 cells, exposed to growth factors. 2. When added individually, nerve growth factor (NGF), basic fibroblast growth factor, and ...
Rizk-Rabin M - - 1994
The epidermis is both a target tissue for and a source of 1,25 dihydroxycholecalciferol. The present study determines which of the epidermal cell populations synthesizes 1,25 dihydroxycholecalciferol and which responds to this hormone. Epidermal keratinocytes from new born rat epidermis were separated by unit gravity sedimentation into poorly differentiated cells, ...
Michel P P - - 1994
The mechanisms that lead ultimately to neuronal death in pathological ageing of the brain remain mostly unknown as in the case of Parkinson's disease where there is a progressive and selective loss of dopaminergic neurons within the substantia nigra. Dopamine-expressing PC12 cells that were neuronally differentiated by nerve growth factor ...
Pintér M - - 1994
Calpain activity of nerve growth factor (NGF)-induced rat pheochromocytoma (PC12) cells shows a transient diminution in the early phase of differentiation. Calpain activity can be further decreased by a cell-permeable calpain inhibitor, calpeptin, which enhances the effect of NGF by stimulating neurite elongation. The number of neurites sprouted by one ...
Castoldi A F - - 1994
Many environmental and occupational chemicals are known to affect the central and/or peripheral nervous system, causing changes that may result in neurological and psychiatric disorders. Because of the limited accessibility of the mammalian nervous tissue, new strategies are being developed to identify biochemical parameters of neuronal cell function, which can ...
Choi E S - - 1994
Treatment of the human neuroblastoma cell line SY5Y with nerve growth factor (NGF) induces terminal neuronal differentiation of a subpopulation of cells which can be selected by treatment with a DNA synthesis inhibitor. We have examined the interactions of naive (untreated) and NGF-differentiated SY5Y cells with laminin, and identified integrin ...
Pierceall W E - - 1994
The Deleted in Colorectal Cancer (DCC) gene is a candidate tumor suppressor gene that is predicted to encode a transmembrane polypeptide with strong similarity to the neural cell adhesion molecule (N-CAM) family. Previous studies have suggested that several different N-CAMs, when expressed in non-neuronal cell types can stimulate neurite outgrowth ...
Hempstead B L - - 1994
The transforming gene of the avian sarcoma virus CT10 encodes a fusion protein (p47gag-crk or v-Crk) containing viral Gag sequences fused to cellular sequences consisting primarily of Src homology regions 2 and 3 (SH2 and SH3 sequences). Here we report a novel function of v-Crk in the mammalian pheochromocytoma cell ...
Goplen D P - - 1994
The hormone 1,25-(OH)2D3 has been shown to modulate cell proliferation and induce differentiation in several normal and malignant cell lines. In this work, we examined the effect of the hormone on the neuroblastoma SK-N-SH cell line. The steroid did not influence cell growth and cell cycle distribution, while retinoic acid ...
Herman M A - - 1994
The nerve growth factor (NGF)-dependent transdifferentiation of adrenal chromaffin cells into sympathetic neurons occurs in two sequential phases: The first phase, in which cells extend neurites and increase proliferation, is mimicked by phorbol myristate acetate (PMA), an activator of protein kinase C. Analogs of cAMP, and forskolin, an activator of ...
Rao L G - - 1994
We studied the effects of 17 beta-estradiol (E2) and PTH on alkaline phosphatase activity in SaOS-2 cells that had been passaged and grown continually in the presence (SaOS + Dex) or absence (SaOS - Dex) of 10(-8) M dexamethasone (Dex). We showed that the more differentiated SaOS + Dex cells ...
Kanthasamy A G - - 1994
Incubation of rat pheochromocytoma (PC12) cells with cyanide (1-10 mM) for 30 min produced a compound which eluted between dopamine (DA) and 3,4-dihydroxyphenylacetic acid in HPLC-EC analysis. Generation of the compound was rapid, concentration-dependent and blocked by pretreatment with clorgyline, a monoamine oxidase A inhibitor. In cell free incubation, the ...
Angus W G - - 1994
Rat pheochromocytoma [PC12] cells were used as models of a dopaminergic system to examine the effects of subchronic exposure to Aroclor 1254 on levels of cellular dopamine in undifferentiated and nerve growth factor (NGF)-stimulated differentiating cells. Either in the absence, or simultaneously in the presence of NGF, exposure to Aroclor ...
Colombo J A - - 1994
Exposure of "in vitro" grown immature and adult adrenal chromaffin cells to concentrations of 10(-3) or 10(-5) M but not 10(-7) M GM1 ganglioside, resulted in significant increase in cell diameter, coupled with reduction of adhesion to substrate within 48 hrs of exposure. None of the GM1 concentrations, with or ...
Buras R R - - 1994
1,25-(OH)2-Vitamin D3, the active metabolite of vitamin D, is a secosteroid hormone with known differentiating activity in leukemic cells. Studies have demonstrated the presence of vitamin D receptors (VDR) in a wide range of tissues and cell types. Antiproliferative activity of 1,25-(OH)2-vitamin D3 has been documented in osteosarcoma, melanoma, colon ...
Gagnon A M - - 1994
Renal calbindin D-28K is a calcium binding protein, localized to the distal nephron, whose expression is reduced in vitamin D deficiency and increased upon administration of 1,25(OH)2D3, the active form of vitamin D. Investigation into the molecular regulation of renal calbindin D-28K expression has been limited by the lack of ...
Lajeunesse D - - 1994
We present evidence that 17 beta-estradiol (17 beta-E2) regulates 1,25(OH)2D3-induced alkaline phosphatase synthesis and osteocalcin secretion by the human osteosarcoma cell line MG-63. When cells were pre-treated with 17 beta-E2 for 48 h prior to treatment with 1,25(OH)2D3 (50 nM) for another 48 h, alkaline phosphatase activity increased by 40% ...
Banerjee A - - 1993
Inhibition of Ca(2+)-activated norepinephrine secretion by the botulinum neurotoxin (NT) serotypes A and E was examined in permeabilized PC12 cells. The dichain type E NT reduced with dithiothreitol (DTT) completely inhibited secretion whereas the dichain type A NT reduced with DTT exhibited incomplete inhibitory activity. In contrast, Ca(2+)-activated secretion in ...
Abbadia Z - - 1993
Thrombospondin (TSP) is a 450-kDa extracellular matrix glycoprotein which supports the growth of human MG-63 osteoblastic cells [Abbadia et al., FEBS Lett., 329 (1993) 341-346]. In this study, we describe the effect of the glucocorticoid, dexamethasone, on cell proliferation and TSP expression by MG-63 cells. Using a serum-free mitogenesis assay, ...
Grando S A - - 1993
To better understand the mechanisms of skin re-epithelization, we developed a simple technique that assays the outgrowth of human keratinocytes. Second-passage foreskin keratinocytes were inoculated at high cell density into 3-mm wells cut from agarose gels in standard 6-well tissue culture dishes. The cells settled on the dish bottom and ...
de la Torre J C - - 1993
We have investigated the replication of lymphocytic choriomeningitis virus (LCMV) before and after the nerve growth factor (NGF)-induced transdifferentiation of PC12 cells from the chromaffin to the neuron-like phenotype. Untreated and NGF-treated cells were equally susceptible to LCMV infection; however, the viral yield was found to be 1,000-fold lower in ...
Sharma N - - 1993
We examined the effect of nerve growth factor (NGF) treatment on expression of a neuronal delayed rectifler K+ channel subtype, Kv2.1 (drk1), in PC12 cells. Anti-Kv2.1 antibodies recognized a single polypeptide population of M(r) = 132 kD in PC12 cell membranes, distinct from the more heterogeneous population found in adult ...
Milani D - - 1993
Rat pheochromocytoma PC12 cells were permanently transfected with a plasmid vector, containing the tat gene of human immunodeficiency virus type 1 (HIV-1). Various clones were obtained showing the production of different levels of bioactive Tat protein (Tat) after transient cotransfection with an HIV-1 long terminal repeat-chloramphenicol acetyltransferase reporter plasmid. Under ...
Kang U J - - 1993
Primary skin fibroblasts were genetically modified with catecholamine-synthesizing enzyme genes and studied as potential syngeneic donor cells to supply catecholamines in animal models of Parkinson's disease. Primary skin fibroblasts obtained from inbred Fischer 344 rats were transduced with tyrosine hydroxylase (TH) or aromatic L-amino acid decarboxylase (AADC) cDNAs using retroviral ...
Pan Z - - 1993
Free radicals are generated in the CNS by ongoing oxygen metabolism and biological events associated with injury and inflammation. Increased free radical levels may also persist in some chronic neurological diseases and in the aged. Nerve growth factor (NGF) is a member of the neurotrophin family of proteins that can ...
Iwami K - - 1993
1. Sodium butyrate increased alkaline phosphatase (ALP) activity of cloned osteoblastic cell line MC3T3-E1 by the stimulation of de novo enzyme synthesis. 2. Sodium butyrate did not affect mature osteoblastic cells but affected preosteoblastic cells. 3. Sodium butyrate decreased tartrate resistant acid phosphatase (TRACP)-positive multinucleated cells (MNC) formation from bone ...
Shackleford G M - - 1993
The product of the Wnt-1 proto-oncogene is a secreted glycoprotein that is normally produced in regions of the embryonic neural tube. We show here that expression of mouse Wnt-1 cDNA in the rat PC12 pheochromocytoma cell line causes a dramatic conversion from a round to a flat cell morphology. In ...
Henderson T A - - 1993
Prior studies indicate that neonatal nerve injury kills many trigeminal (V) first- and second-order cells, and interrupts pattern formation in the brainstem and cerebral cortex. Yet it is not known whether effects upon cell survival and pattern formation are causally related. To determine whether axotomized V ganglion cells can be ...
Keilbaugh S A - - 1993
A strategy for preventing or delaying the peripheral neuropathy induced by 2',3'-dideoxycytidine (ddC) therapy in patients with acquired immunodeficiency syndrome was suggested by findings, in two laboratories, that cultured avian and mammalian cells devoid of mitochondrial DNA continue to replicate at virtually normal rates, provided that the medium is supplemented ...
Zompa E A - - 1993
To test the hypothesis that transplanted neuronal or neuronal-like cell lines, grown in vitro, might survive and differentiate in the mammalian spinal grey matter, adult male Sprague-Dawley rats (N = 5) were injected with a suspension of between 3 x 10(5) and 1.0 x 10(6) DiI labeled, undifferentiated rat pheochromocytoma ...
Fahnestock M - - 1993
Mouse submandibular gland (SMG) cells in culture rarely retain functional properties of SMG cells in vivo. We demonstrate that both primary SMG cells and the mouse SMG cell line SCA-9 secrete biologically active nerve growth factor (NGF). However, primary cells secrete 40-fold more NGF than SCA-9 cells, demonstrating that SCA-9 ...
Trydal T - - 1993
An unacceptable loss of tritiated 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] to the wall of the reaction tubes constituted an obstacle when examining C3H/10T1/2 Cl 8 cells for 1,25-(OH)2D3 receptor. The loss of tracer in low protein cell extracts could be strongly reduced by incubating the cell extracts in polyethylene tubes and in ...
Christensen L R - - 1993
Evidence is accumulating that nerve growth factor receptor (NGF-R or p75NGFR) can mediate cell growth and differentiation of non-neuronal cells. NGF-R expression was studied in developing teeth of human embryos and fetuses between the 6th and 18th weeks of gestation, using a monoclonal mouse-anti-human NGF-R antibody. In contrast to earlier ...
Pittman R N - - 1993
A model system has been established in which PC12 cells are converted to neuronal-like cells that undergo transcription-dependent cell death following removal of NGF. Nineteen sublines of PC12 cells were tested to establish parameters for making cells dependent on NGF for survival. In most sublines, a relatively small percentage of ...
Carraway R E - - 1993
Neurotensin (NT) is coexpressed with catecholamines in sympathetic neurons and adrenal chromaffin cells. A pheochromocytoma PC12 cell line can also be induced to express the NT gene and produce immunoreactive NT. In the present study, NT mRNA was quantified under various hormonal conditions and NT precursor synthesis rates were determined ...
Zhong L T - - 1993
Glutamate has been shown, at high concentrations (5-10 mM), to lead to death in cells of the pheochromocytoma cell line PC12. We report that similar concentrations of glutamate also kill immortalized central neural cell lines, and that the expression of the proto-oncogene bcl-2 in these cell lines blocks glutamate neurotoxicity. ...
Rovere C - - 1993
Neurotensin and neuromedin N are two biologically active, related peptides that are encoded in the same precursor molecule. In the rat, the precursor consists of a 169-residue polypeptide containing in its C-terminal region one copy each of neurotensin and neuromedin N. Four Lys-Arg sequences, which are thought to represent putative ...
Falcione M - - 1993
Neocarzinostatin is an antineoplastic agent that induces differentiated morphology in human (SK-N-SH) neuroblastoma cells in culture. We have compared this morphological differentiation with that induced by the endogenous differentiation inducer, nerve growth factor (NGF), and have explored the effects of exposure to NGF upon the morphological changes induced by neocarzinostatin ...
Inoue D - - 1993
Human T cell lymphotrophic virus, type I (HTLV-I)-infected T cells overproduce parathyroid hormone-related peptide (PTHRP) and cause hypercalcemia in patients with adult T cell leukemia. The present study was undertaken to test whether 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) and its noncalcemic analogue, 22-oxa-1,25-(OH)2D3 (OCT), could suppress cell proliferation and PTHRP gene expression ...
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