Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The purpose of these experiments is to test whether the differences between normal and tetrodotoxin-resistant Na+ channels reside in the selectivity filter. To do this, we have compared the selectivity of batrachotoxin-activated channels for alkali cations, organic cations, and nonelectrolytes in two neuroblastoma clonal cell lines: N18, which has normal tetrodotoxin (TTX) sensitivity, and C9, which is relatively TTX-resistant. We have also studied the effect of H+ on Na+ permeability and on the interaction between TTX and its receptor site in both cell lines. There is no qualitative difference between the two cell lines in any of these properties. In both cell lines the batrachotoxin-activated Na+ channels have a selectivity sequence of Tl+ greater than Na+ greater than K+, guanidinium greater than Rb+ greater than Cs+, methylamine. Also, in both cell lines H+ blocks Na+ channels with a pKa of 5.5 and inhibits the action of TTX with the same pKa. These observations indicate that the selectivity filters of the Na+ channels in C9 and N18 do not differ significantly despite the 100-fold difference in TTX-affinity. Our selectivity studies of batrachotoxin-activated Na+ channels for both cell lines suggest that these toxin-activated Na+ channels have a limiting pore size of 3.8 x 6.0 A, as compared to a pore size of 3.0 x 5.0 A for potential-activated Na+ channels.
J Gen Physiol 1979 Jun
PMID:Comparison of ionic selectivity of batrachotoxin-activated channels with different tetrodotoxin dissociation constants. 3 11

The nature of the restriction of herpes simplex virus replication in C 1300 neuroblastoma cells was studied. A low rate of adsorption was observed, probably due to the relatively few receptors for HSV on plasma membranes of C 1300 cells. The penetration rate of HSV to the nucleus was slow with an impaired processing of attached virus from plasma membrane to cell nucleus. Even at a high multiplicity of infection only a low percentage of the C 1300 neuroblastoma cells was permissively infected as determined by infectious centre assays. The yield of infectious HSV per virus-producing C 1300 cell was 1% of the yield from GMK control cells. The restriction in neuroblastoma cells of HSV infection could not be accounted for by sensitivity of cells to interferon or by an efficient induction of interferon. Evidence was obtained for the presence in C 1300 cells of an inhibitor of HSV replication not compatible with classical interferon. Observations on C 1300 cells maintaining many characteristics of differentiated neurons suggest that these cells may be useful as a model for studies on HSV-neuron interactions.
J Gen Virol 1978 May
PMID:Herpes simplex virus infection of in vitro cultured neuronal cells (mouse neuroblastoma C 1300 cells). 20 58

Scrapie strain replication in the nerve growth factor-induced, differentiated PC12 cell culture system was examined. Differences in replication between mouse-derived agents were demonstrated, with the 139A scrapie strain yielding 100- to 1000-fold higher levels of infectivity than the ME7 scrapie strain. Replication was not detected in PC12 cells infected with either the hamster-derived 263K or rat-derived 139R scrapie strains. Studies on the neurotransmitters in infected PC12 cells demonstrated that the adrenergic pathway was unchanged but the cholinergic pathway was altered. Furthermore, the degree of alteration correlated with the level of scrapie strain replication. Comparison of infectivity titres and enzymatic changes in ME7-infected PC12 cells with those in Chandler agent-infected mouse neuroblastoma cells suggests that the significant changes in neurotransmitter levels in cultures exhibiting low titres of infectivity involve factors in addition to strain replication. The variation in the range of scrapie strain replication in PC12 cells is discussed in relationship to species barrier, cell targeting, genetic susceptibility and species strain specificity. These studies further emphasize the value of the PC12 cell model system in examining the scrapie strain-host cell interaction and in addition support the concept of variation among scrapie strains.
J Gen Virol 1992 Nov
PMID:Demonstration of scrapie strain diversity in infected PC12 cells. 135 2

1. SH-SY5Y, a human neuroblastoma cell line, was used as a tissue culture model to examine the hypothesis that cocaine may affect the metabolism of tau protein which stabilizes microtubules and promotes microtubule assembly. 2. Cocaine hydrochloride (10(-9)-10(-3) M) caused dose-dependent reductions in cell number, with 10(-3) M causing 28% reduction after 48 hr. 3. This drug also decreased tau protein (50 Kd) in the cytoplasmic (supernatant) as well as the membrane (pellet) fraction after 48-hr treatment.
Gen Pharmacol 1992 Nov
PMID:Microtubular tau protein after cocaine in cultured SH-SY5Y human neuroblastoma. 148 20

1. A human neuroblastoma cell line, SH-SY5Y, was used to study the effects of phencyclidine (PCP) on microtubule-associated tau protein, which acts in vivo chiefly to induce the assembly of tubulin and in vitro to promote microtubule polymerization. 2. PCP (1.0 mM) decreased tau protein (50 kD) in the cytoplasmic (supernatant) fraction as well as in the membrane (pellet) fraction. 3. These changes in tau protein were accompanied by decreases of 30-95% in cell number after concentrations of PCP, 0.25-1.0 mM, respectively. 4. After 0.5 mM PCP cytoplasmic and membrane fractions of SH-SY5Y cells showed 100 and 84% increases in total protein, respectively.
Gen Pharmacol 1992 May
PMID:Changes in microtubule-associated tau protein in human neuroblastoma cells after phencyclidine. 151 52

By using a retrovirus expression vector, pZIP-NeoSV(X)1, we introduced a cloned cDNA of the rabies virus G gene into BHK-21 cells and the NA cell clone originated from the murine neuroblastoma C1300 line. Using the neomycin resistance gene of the vector, we isolated several G418-resistant transformants of BHK-21 and NA cells (referred to as G-BHK and G-NA cells, respectively). G-BHK cells constitutively produced G proteins, whereas G-NA cells produced the proteins only when treated with sodium butyrate. G proteins synthesized in these transformants were transported normally to the surface of the cell, but they displayed different electrophoretic mobilities, which were shown to originate from differences in the number and structure of the carbohydrate moieties of the protein; G-BHK cells produced highly glycosylated and sialylated G proteins, whereas less glycosylated and much less sialylated G proteins were produced by G-NA cells as observed in virus-infected NA and BHK-21 cells, indicating that the glycosylation and sialylation of the G protein depend on the cellular conditions under which the protein was produced. In the absence of sodium butyrate the G protein was not detectable in G-NA cells either by immunoblot assay or fluorescent antibody staining, but the cells were fairly sensitive to syngeneic rabies virus-specific cytotoxic T lymphocytes, although the sensitivity was much increased by treatment with sodium butyrate.
J Gen Virol 1992 Feb
PMID:Comparison of rabies virus G proteins produced by cDNA-transfected animal cells that display either inducible or constitutive expression of the gene. 153 91

Human immunodeficiency virus type 1 (HIV-1) infection was studied in two different human neuroblastoma cell lines, SK-N-MC and SH-SY5Y. Results from immunofluorescence analysis indicate that SK-N-MC cells express a 68K neurofilament, and SH-SY5Y cells express additionally a 160K to 200K neurofilament complex and thus represent a more differentiated state. HIV-1 infection in these cell lines was demonstrated by nested polymerase chain reaction and further characterized by in situ hybridization, which showed that about 50% of SK-N-MC cells and 20% of SH-SY5Y cells were infected by HIV-1 and contained integrated proviral HIV-1 DNA. Among the cytokines and growth factors studied, tumour necrosis factor alpha (TNF-alpha) enhanced virus production in both cell lines, but to a differing extent, according to our mRNA and p24 antigen capture assay. In SK-N-MC cells the enhancement of HIV-1 mRNA was detected after 24 h of stimulation, and declined to the control level by 48 h. In SH-SY5Y cells a clear-cut stimulation was seen at both time points. By contrast, interleukin-6 (IL-6) enhanced the virus replication only in SK-N-MC cells, as shown at the mRNA level. Immunochemical staining showed no differences in the proportion of HIV-1-positive cells after 48 h of stimulation by TNF-alpha or IL-6 when compared to the control cells. In addition, based on a thymidine incorporation assay, TNF-alpha inhibited, but IL-6 strongly increased, the DNA synthesis in SK-N-MC cells, whereas in the SH-SY5Y cell line no such differences were seen. We discuss the possibility that developing, less-differentiated neurons may be more readily infected by HIV-1 than fully differentiated neurons, and that cytokines such as TNF-alpha and IL-6, which are elevated in HIV-1-infected individuals, may enhance HIV production.
J Gen Virol 1992 Jul
PMID:Activation of integrated human immunodeficiency virus type 1 in human neuroblastoma cells by the cytokines tumour necrosis factor alpha and interleukin-6. 162

The electrophysiological properties of a human neuroblastoma cell line, LA-N-5, were studied with the whole-cell configuration of the patch clamp technique before and after the induction of differentiation by retinoic acid, a vitamin A metabolite. Action potentials could be elicited from current clamped cells before the induction of differentiation, suggesting that some neuroblasts of the developing sympathetic nervous system are excitable. The action potential upstroke was carried by a sodium conductance, which was composed of two types of sodium currents, described by their sensitivity to tetrodotoxin (TTX) as TTX sensitive and TTX resistant. TTX-sensitive and TTX-resistant sodium currents were blocked by nanomolar and micromolar concentrations of TTX, respectively. The voltage sensitivity of activation and inactivation of TTX-resistant sodium current is shifted -10 to -30 mV relative to TTX-sensitive sodium current, suggesting that TTX-resistant sodium current could play a role in the initiation of action potentials. TTX-sensitive current comprised greater than 80% of the total sodium current in undifferentiated LA-N-5 cells. The surface density of total sodium current increased from 24.9 to 57.8 microA/microF after cells were induced to differentiate. The increase in total sodium current density was significant (P less than 0.05). The surface density of TTX-resistant sodium current did not change significantly during differentiation, from which we conclude that an increase in TTX-sensitive sodium current underlies the increase in total current.
J Gen Physiol 1991 Mar
PMID:Sodium currents during differentiation in a human neuroblastoma cell line. 164 94

Blood plasma, serum and its fractions containing components of different molecular weights as well as some identified serum constituents were tested for their action on sodium currents of voltage-clamped, internally dialyzed neuroblastoma cells. Only components with a molecular weight over 50 kDa produced a persistent increase in sodium channel currents (stimulatory effect) and shifts in activation and inactivation curves along the voltage axis towards more negative or positive potentials, respectively (modifying effect). Both modulations taken together provide a somewhat higher level of sodium electro-excitable system activity. Among the identified serum components tested, including those possessing high physiological activity, albumin was the only one which reproduced the effects of whole blood serum both qualitatively and quantitatively. The data obtained allow to assume albumin to play a role of an active substance responsible for the blood plasma or serum effects on the potential-dependent transporting system in the neuroblastoma cell membrane. Albumin seems to be involved in holding the functional activity of sodium channels on a suitable level rather than being involved in any regulatory processes.
Gen Physiol Biophys 1991 Aug
PMID:The action of blood serum and its components on potential-dependent sodium channels in neuroblastoma cells. 166 55

We have previously shown that the herpes simplex virus type 1 (HSV-1)-specified glycoprotein C (gC-1) produced in epitheloid cells contains epitopes of peptide nature, which are dependent on galactose of oligosaccharides for their expression. In the present communication we report that these epitopes are expressed in a mouse neuroblastoma cell line (C1300) with low levels of galactosyl transferases. However, in place of galactose the glycoprotein from C1300 cells was found to contain oligosaccharides with additional fucose units. Fucosidase treatment, but not galactosidase treatment, abolished the antigenic activity of the carbohydrate-dependent epitopes. Altogether the results indicated that the carbohydrate-dependent epitopes of gC-1 from C1300 cells were stabilized by peripheral sugars of N-linked oligosaccharides rather than O-linked ones and that fucose could substitute for terminal galactose in promoting the activity of the carbohydrate-dependent epitopes. This is the first demonstration of the involvement of fucose in the establishment of a carbohydrate-dependent epitope of peptide nature. The results also demonstrated that reversible carbohydrate-peptide interactions were responsible for the activity of the carbohydrate-dependent epitopes.
J Gen Virol 1990 Apr
PMID:Activity of herpes simplex virus type 1-specified glycoprotein C antigenic site II epitopes reversibly modulated by peripheral fucose or galactose units of glycoprotein oligosaccharides. 169 Dec 70


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