16 results on '"Verdonck, F."'
Search Results
2. The age-dependent expression of the F18(+) E.coli receptor on porcine gut epithelial cells is positively correlated with the presence of histo-blood group antigens
- Author
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Coddens, Annelies, VERDONCK, F, Tiels, Petra, Rasschaert, Kristien, Goddeeris, Bruno, and Cox, Eric
- Subjects
Medicine and Health Sciences - Published
- 2007
3. Comparison of immune responses in parenteral FaeG DNA primed pigs boosted orally with F4 protein or reimmunized with the DNA vaccine
- Author
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Melkebeek, Vesna, VERDONCK, F, Goddeeris, Bruno, and Cox, Eric
- Subjects
Medicine and Health Sciences - Published
- 2007
4. Enterotoxigenic Escherichia coli (K88) induce proinflammatory responses in porcine intestinal epithelial cells.
- Author
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Devriendt B, Stuyven E, Verdonck F, Goddeeris BM, and Cox E
- Subjects
- Animals, Animals, Newborn, Antigens, Bacterial genetics, Bacterial Adhesion genetics, Cell Line, Diarrhea, Enterotoxigenic Escherichia coli pathogenicity, Escherichia coli Infections microbiology, Escherichia coli Infections physiopathology, Escherichia coli Proteins genetics, Fimbriae Proteins genetics, Flagellin metabolism, Inflammation, Interleukin-6 metabolism, Interleukin-8 metabolism, Intestinal Mucosa immunology, Intestinal Mucosa microbiology, Intestinal Mucosa pathology, Mutant Proteins genetics, Protein Engineering, Swine, Toll-Like Receptor 5 immunology, Toll-Like Receptor 5 metabolism, Virulence Factors, Antigens, Bacterial metabolism, Enterotoxigenic Escherichia coli immunology, Escherichia coli Infections immunology, Escherichia coli Proteins metabolism, Fimbriae Proteins metabolism, Intestinal Mucosa metabolism, Mutant Proteins metabolism
- Abstract
Infections with F4(+) enterotoxigenic Escherichia coli (ETEC) causes severe diarrhoea in piglets, resulting in morbidity and mortality. F4 fimbriae are the key virulence factors mediating the attachment of F4(+) ETEC to the intestinal epithelium. Intestinal epithelial cells (IEC) are recently being recognized as important regulators of the intestinal immune system through the secretion of cytokines, however, data on how F4(+) ETEC affect this cytokine secretion are scarce. By using ETEC strains expressing either polymeric, monomeric or F4 fimbriae with a reduced polymeric stability, we demonstrated that polymeric fimbriae are essential for adhesion to porcine IEC and the secretion of IL-6 and IL-8 by IEC. Remarkably, this cytokine secretion was not abrogated following stimulation with an F4-negative strain. Since this strain expresses flagellin, TLR5 mediated signalling could be involved. Indeed, porcine IEC express TLR5 and purified flagellin induced IL-6 and IL-8 secretion, indicating that, as for other pathogens, flagellin is the dominant virulence factor involved in the induction of proinflammatory responses in IEC. These results indicate a potential mucosal adjuvant capacity of ETEC-derived flagellin and may improve rational vaccine design against F4(+) ETEC infections., (Copyright © 2010 Elsevier Ltd. All rights reserved.)
- Published
- 2010
- Full Text
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5. The polymeric stability of the Escherichia coli F4 (K88) fimbriae enhances its mucosal immunogenicity following oral immunization.
- Author
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Verdonck F, Joensuu JJ, Stuyven E, De Meyer J, Muilu M, Pirhonen M, Goddeeris BM, Mast J, Niklander-Teeri V, and Cox E
- Subjects
- Adhesins, Escherichia coli metabolism, Administration, Oral, Animals, Animals, Suckling, Escherichia coli Infections immunology, Escherichia coli Infections microbiology, Escherichia coli Infections prevention & control, Escherichia coli Infections veterinary, Escherichia coli Vaccines administration & dosage, Escherichia coli Vaccines immunology, Immunity, Mucosal, Immunization, Mutation, Polymers metabolism, Swine, Swine Diseases microbiology, Adhesins, Escherichia coli chemistry, Enterotoxigenic Escherichia coli immunology, Fimbriae, Bacterial chemistry, Fimbriae, Bacterial immunology, Fimbriae, Bacterial metabolism, Intestinal Mucosa immunology, Polymers chemistry, Swine Diseases immunology
- Abstract
Only a few vaccines are commercially available against intestinal infections since the induction of a protective intestinal immune response is difficult to achieve. For instance, oral administration of most proteins results in oral tolerance instead of an antigen-specific immune response. We have shown before that as a result of oral immunization of piglets with F4 fimbriae purified from pathogenic enterotoxigenic Escherichia coli (ETEC), the fimbriae bind to the F4 receptor (F4R) in the intestine and induce a protective F4-specific immune response. F4 fimbriae are very stable polymeric structures composed of some minor subunits and a major subunit FaeG that is also the fimbrial adhesin. In the present study, the mutagenesis experiments identified FaeG amino acids 97 (N to K) and 201 (I to V) as determinants for F4 polymeric stability. The interaction between the FaeG subunits in mutant F4 fimbriae is reduced but both mutant and wild type fimbriae behaved identically in F4R binding and showed equal stability in the gastro-intestinal lumen. Oral immunization experiments indicated that a higher degree of polymerisation of the fimbriae in the intestine was correlated with a better F4-specific mucosal immunogenicity. These data suggest that the mucosal immunogenicity of soluble virulence factors can be increased by the construction of stable polymeric structures and therefore help in the development of effective mucosal vaccines.
- Published
- 2008
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6. The excretion of F18+ E. coli is reduced after oral immunisation of pigs with a FedF and F4 fimbriae conjugate.
- Author
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Tiels P, Verdonck F, Coddens A, Goddeeris B, and Cox E
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- Adhesins, Bacterial immunology, Administration, Oral, Animals, Bacterial Vaccines administration & dosage, Diarrhea prevention & control, Edema Disease of Swine immunology, Escherichia coli immunology, Escherichia coli metabolism, Escherichia coli Infections prevention & control, Escherichia coli Proteins immunology, Fimbriae Proteins metabolism, Fimbriae, Bacterial immunology, Fimbriae, Bacterial metabolism, Immunization, Swine, Vaccines, Conjugate immunology, Weaning, Bacterial Vaccines immunology, Diarrhea veterinary, Escherichia coli genetics, Escherichia coli Infections veterinary, Fimbriae Proteins immunology
- Abstract
Currently, no vaccines are available for edema disease and post-weaning diarrhoea (PWD) in pigs. In the present study, a subunit vaccine containing the F18 fimbrial adhesin FedF was studied. Hereto, recombinant FedF was produced as a fusion protein with maltose-binding protein. Even though the produced MBPFedF was shown to attach in vitro to enterocytes, almost no FedF-specific immune response could be detected after oral administration to piglets. The delivery of FedF to the intestinal mucosa was improved by conjugating the MBPFedF to F4 fimbriae. Indeed, this conjugation induced a systemic and local FedF-specific immune response and led to a reduction in excretion after infection with F18+ E. coli. Although complete protection was not observed, the conjugation between FedF and F4 fimbriae can be considered as a first step towards the development of a combined vaccine against F4+ and F18+ E. coli infections.
- Published
- 2008
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7. Plasmid-encoded GM-CSF induces priming of the F4(K88)-specific serum IgA response by FaeG DNA vaccination in pigs.
- Author
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Melkebeek V, Verdonck F, Stuyven E, Goddeeris B, and Cox E
- Subjects
- Animals, Cell Proliferation, Granulocyte-Macrophage Colony-Stimulating Factor genetics, Lymphocytes cytology, Vaccines, DNA immunology, Adhesins, Escherichia coli genetics, Granulocyte-Macrophage Colony-Stimulating Factor pharmacology, Immunoglobulin A blood, Plasmids, Vaccines, DNA administration & dosage
- Abstract
We have used FaeG DNA to immunise piglets by the intradermal (ID) and the intramuscular (IM) route in a heterologous prime/boost model. ID immunisation with DNA resulted in a better induction of cellular immunity, whereas only the IM immunisation could prime an F4(K88)-specific serum IgA response. However, ID administration of plasmid-encoded GM-CSF 1 week before the ID immunisation enhanced the F4-specific humoral and cellular immune response and even primed the F4-specific IgA response more efficiently than the IM immunisation did.
- Published
- 2006
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8. The jejunal Peyer's patches are the major inductive sites of the F4-specific immune response following intestinal immunisation of pigs with F4 (K88) fimbriae.
- Author
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Snoeck V, Verfaillie T, Verdonck F, Goddeeris BM, and Cox E
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- Animals, Antibodies, Bacterial biosynthesis, Antibodies, Bacterial blood, Antibody-Producing Cells immunology, Antigens, Bacterial administration & dosage, Escherichia coli immunology, Escherichia coli Proteins administration & dosage, Fimbriae Proteins administration & dosage, Immunoglobulin A biosynthesis, Immunoglobulin A blood, Immunoglobulin G biosynthesis, Immunoglobulin G blood, Immunoglobulin M biosynthesis, Immunoglobulin M blood, Models, Animal, Swine, Antigens, Bacterial immunology, Escherichia coli Proteins immunology, Fimbriae Proteins immunology, Jejunum immunology, Peyer's Patches immunology
- Abstract
A recently developed oral immunisation model in pigs in which F4 (K88) fimbriae of enterotoxigenic Escherichia coli are administered to induce a protective intestinal immunity, was used to determine the optimal inductive sites of the F4-specific intestinal immune response. Hereto, pigs were immunised with F4 orally, in the lumen of the mid-jejunum, ileum or mid-colon. Throughout the small intestine, the highest number of ASC was found following jejunal immunisation, followed by ileal, oral and colonic immunisation. To determine the signifance of Peyer's patches in the induced immune response, F4 was injected into the jejunal Peyer's patches (JPP), lamina propria (LP) and ileal Peyer's patches (IPP). Immunisation in the JPP induced the highest number ASC in the small intestine, whereas immunisation in the LP and IPP resulted in lower intestinal antibody responses. In conclusion, we have shown that the JPP are the major inductive sites of the F4-specific intestinal antibody response. This knowledge could be important when using the pig as an animal model for vaccination studies.
- Published
- 2006
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9. F4 (K88) fimbrial adhesin FaeG expressed in alfalfa reduces F4+ enterotoxigenic Escherichia coli excretion in weaned piglets.
- Author
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Joensuu JJ, Verdonck F, Ehrström A, Peltola M, Siljander-Rasi H, Nuutila AM, Oksman-Caldentey KM, Teeri TH, Cox E, Goddeeris BM, and Niklander-Teeri V
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- Adhesins, Escherichia coli genetics, Animals, Feces microbiology, Immunization, Medicago sativa genetics, Swine, Weaning, Adhesins, Escherichia coli immunology, Escherichia coli Vaccines immunology, Vaccines, Synthetic immunology
- Abstract
Transgenic plants are attractive bioreactors to large-scale production of recombinant proteins because of their relatively low cost. This study reports for the first time the use of transgenic plants to reduce enterotoxigenic Escherichia coli (ETEC) excretion in its natural host species. The DNA sequence encoding the major subunit and adhesin FaeG of F4+ ETEC was transformed into edible alfalfa plants. Targeting of FaeG production to chloroplasts led to FaeG levels of up to 1% of the total soluble protein fraction of the transgenic alfalfa. Recombinant plant-produced FaeG (pFaeG) remained stable for 2 years when the plant material was dried and stored at room temperature. Intragastric immunization of piglets with pFaeG induced a weak F4-specific humoral response. Co-administration of pFaeG and the mucosal adjuvant cholera toxin (CT) enhanced the immune response against FaeG, reflected a better induction of an F4-specific immune response. In addition, the intragastric co-administration of CT with pFaeG significantly reduced F4+ E. coli excretion following F4+ ETEC challenge as compared with pigs that had received nontransgenic plant material. In conclusion, transgenic plants producing the FaeG subunit protein could be used for production and delivery of oral vaccines against F4+ ETEC infections.
- Published
- 2006
- Full Text
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10. Oral immunization of piglets with recombinant F4 fimbrial adhesin FaeG monomers induces a mucosal and systemic F4-specific immune response.
- Author
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Verdonck F, Cox E, Van der Stede Y, and Goddeeris BM
- Subjects
- Adhesins, Bacterial administration & dosage, Adhesins, Bacterial chemistry, Adhesins, Escherichia coli administration & dosage, Adhesins, Escherichia coli chemistry, Administration, Oral, Animals, Antibodies, Bacterial analysis, Bacterial Vaccines administration & dosage, Bacterial Vaccines chemistry, Blotting, Western, Enzyme-Linked Immunosorbent Assay, Escherichia coli chemistry, Escherichia coli immunology, Escherichia coli Infections immunology, Escherichia coli Infections prevention & control, Feces microbiology, Immunization, Immunoglobulin A analysis, Immunoglobulin A biosynthesis, Immunoglobulin G analysis, Immunoglobulin G biosynthesis, Immunoglobulin M analysis, Immunoglobulin M biosynthesis, Swine immunology, Vaccines, Synthetic analysis, Vaccines, Synthetic chemistry, Vaccines, Synthetic immunology, Adhesins, Bacterial immunology, Adhesins, Escherichia coli immunology, Antibodies, Bacterial biosynthesis, Antibody Formation immunology, Bacterial Vaccines immunology, Immunity, Mucosal immunology
- Abstract
The importance of adhesins in the pathogenicity of several bacteria resulted in studies on their usefulness in vaccines. In this study, the gene of the F4(K88)-fimbrial adhesin FaeG of the pathogenic enterotoxigenic Escherichia coli (ETEC) strain GIS26 was cloned in the pET30Ek-LIC vector and expressed with an N-terminal His- and S-tag in the cytoplasm of BL21(DE3). Recombinant FaeG (rFaeG) subunits were isolated from insoluble cytoplasmic aggregates and refolded into a native-like F4 receptor (F4R)-binding conformation. Indeed, the presence of conformational epitopes was shown by ELISA and the ability to bind the F4R was observed by inhibiting the adhesion of F4+ ETEC to F4R+ villi with increasing concentrations of native-like refolded rFaeG subunits. The rFaeG subunits appear as monomers, whereas the purified F4 fimbriae are multimers. Oral immunization of newly weaned piglets with native-like rFaeG induced a mucosal and systemic F4-specific immune response, significantly reducing F4+ E. coli excretion from 2 till 5 days following challenge infection. However, improvement of stability and immunogenicity of rFaeG is necessary since a higher F4-specific response was obtained following immunization with purified F4 fimbriae. Furthermore, the N-terminal fusion of a His- and S-tag was not detrimental for binding the F4R, supporting the use of FaeG as mucosal carrier. In conclusion, oral immunization with a recombinant fimbrial adhesin subunit of Escherichia coli induces a mucosal and systemic fimbriae-specific immune response.
- Published
- 2004
- Full Text
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11. Priming of piglets against enterotoxigenic E. coli F4 fimbriae by immunisation with FAEG DNA.
- Author
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Verfaillie T, Melkebeek V, Snoek V, Douterlungne S, Cox E, Verdonck F, Vanrompay D, Goddeeris B, and Cox E
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- Animals, Antibodies, Bacterial analysis, Antibodies, Bacterial biosynthesis, Antibody Formation immunology, Antibody Specificity, B-Lymphocytes immunology, Biolistics, COS Cells, Cell Division, Chlorocebus aethiops, Enterotoxins genetics, Escherichia coli genetics, Fimbriae, Bacterial genetics, Immunization, Lymphocytes immunology, Lymphocytes physiology, Plasmids genetics, Plasmids immunology, Swine, Vaccines, DNA immunology, Bacterial Vaccines immunology, DNA, Bacterial immunology, Enterotoxins immunology, Escherichia coli immunology, Fimbriae, Bacterial immunology
- Abstract
Early vaccination is necessary to protect pigs against postweaning diarrhoea caused by enterotoxigenic Escherichia coli (ETEC). However, at present no commercial vaccine allows successful vaccination. This is partly due to the presence of maternally derived antibodies. Since DNA vaccines are suggested to be superior to protein vaccines in young animals with maternal antibodies, we determined whether the fimbrial adhesin (FaeG) of F4ac(+) ETEC could be used as a plasmid DNA vaccine to prime piglets in a heterologous prime-boost approach. Hereto, pcDNA1/faeG19 was constructed and expression of rFaeG in Cos-7 cells was demonstrated. Thereafter, pigs were immunised (days 0, 21 and 42) intramuscularly by injection or intradermally by gene gun and humoral and cellular immune responses were analysed. Even though responses were low, results demonstrated that intramuscular injection was superior to gene gun delivery for priming the humoral immune response since higher antibody titres were raised, whereas gene gun delivery better induced a cellular response, evaluated by a lymphocyte proliferation assay. Effective priming of the humoral immune response was evidenced by high IgG titres 1 week after a protein boost with purified F4. The low responses to the pcDNA1/faeG19 DNA vaccination suggest that delivery of the DNA and/or the expression of the faeG gene should be improved.
- Published
- 2004
- Full Text
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12. Reduced faecal excretion of F4+-E coli by the intramuscular immunisation of suckling piglets by the addition of 1alpha,25-dihydroxyvitamin D3 or CpG-oligodeoxynucleotides.
- Author
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Van der Stede Y, Cox E, Verdonck F, Vancaeneghem S, and Goddeeris BM
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- Adjuvants, Immunologic administration & dosage, Animals, Animals, Suckling, Antibodies, Bacterial blood, Escherichia coli immunology, Escherichia coli pathogenicity, Escherichia coli Infections immunology, Escherichia coli Infections microbiology, Escherichia coli Infections prevention & control, Feces microbiology, Fimbriae, Bacterial immunology, Immunity, Mucosal, Injections, Intramuscular, Lymphocyte Activation, Sus scrofa, Swine Diseases immunology, Swine Diseases microbiology, Weight Gain, Calcitriol administration & dosage, Escherichia coli isolation & purification, Escherichia coli Infections veterinary, Escherichia coli Vaccines administration & dosage, Oligodeoxyribonucleotides administration & dosage, Swine Diseases prevention & control
- Abstract
In this study it was analysed whether intramuscular (IM) immunisation of piglets with F4 during the suckling period could protect against oral challenge with F4(+)-Escherichia coli and whether addition of 1alpha,25(OH)(2)D(3) or CpG-ODN could improve this protection.F4-seronegative F4-receptor positive pigs were divided into four groups of five pigs each. The pigs were intramuscularly injected with F4 fimbriae only or supplemented with 1alpha,25(OH)(2)D(3) (D(3)-group) or CpG-ODN (CpG-group). The control group received PBS in IFA. Seven days after the second immunisation, all pigs were intragastrically inoculated with 1 x 10(10) CFU of F4(+)-E. coli. All F4-injected groups, showed a reduced faecal excretion of F4(+)-E. coli. However, this reduction was only statistically significant in the D(3)-group 2 days post challenge. Pigs in the latter group showed a secondary antibody response upon challenge, indicating that F4-primed memory B-cells were present in the gut-associated lymphoid tissues at that moment.CpG-ODN, on the other hand, did not enhance the F4-specific antibody response. However, CpG-ODN significantly increased the F4-specific as well as mitogen-induced proliferation of peripheral blood monomorphonuclear cells indicating a direct or indirect overall effect on T-lymphocytes. In conclusion, supplementation with 1alpha,25(OH)(2)D(3) or CpG-ODN improved protection against an F4(+)-E. coli infection. This protection was most obvious for 1alpha,25(OH)(2)D(3) and indicates its potential use in veterinary vaccines against enteropathogens.
- Published
- 2003
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13. Different kinetic of antibody responses following infection of newly weaned pigs with an F4 enterotoxigenic Escherichia coli strain or an F18 verotoxigenic Escherichia coli strain.
- Author
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Verdonck F, Cox E, van Gog K, Van der Stede Y, Duchateau L, Deprez P, and Goddeeris BM
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- Animals, Antibodies, Bacterial blood, Bacterial Adhesion, Escherichia coli growth & development, Escherichia coli Infections immunology, Escherichia coli Infections microbiology, Escherichia coli Proteins immunology, Fimbriae Proteins immunology, Immunity, Mucosal, Immunoglobulin A biosynthesis, In Vitro Techniques, Intestinal Mucosa immunology, Intestinal Mucosa microbiology, Kinetics, Species Specificity, Sus scrofa, Antibodies, Bacterial biosynthesis, Escherichia coli immunology, Escherichia coli pathogenicity
- Abstract
To develop a vaccine against Escherichia coli-induced post-weaning diarrhea and edema disease, insights in the induction of the protective immune response following infection with these pathogenic E. coli is needed. Therefore, the fimbriae-specific antibody response of newly weaned pigs following infection with the Shiga-like toxin type II variant (SLT-IIv) producing F18(+) verotoxigenic E. coli (VTEC) (strain 107/86) was compared with the response following an infection with LT producing F4(+) enterotoxigenic E. coli (ETEC) (strain GIS 26). F4(+) ETEC were able to colonize the gut very soon after infection, as peak excretion of F4(+) E. coli bacteria was seen 2 days post-infection (dpi), but had already disappeared 7dpi. On the other hand, F18(+) VTEC infection resulted in a slower colonization of the gut as the peak excretion of F18(+) E. coli was observed between 3 and 5dpi, but this colonization remained longer as F18(+) E. coli were detected till 9dpi in feces. Furthermore, this fast colonization pattern of F4(+) ETEC is accompanied with the presence of F4-specific antibodies in mucosal tissues and serum from 4dpi onward, with maximal amounts of F4-specific IgA in the jejunal lamina propria and serum 7dpi. In contrast, F18-specific IgA was only readily detected in the jejunal lamina propria 15dpi and showed a maximum serum titer 21dpi. Besides this faster induction and higher antibody response, the switch from IgM to IgA and IgG was also earlier following the F4(+) ETEC infection.
- Published
- 2002
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14. Neurospecificity of phyto-bufadienolides is not related to differences in Na+/K+ pump inhibition.
- Author
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Van der Walt JJ, Van Rooyen JM, Kellerman TS, Carmeliet EE, and Verdonck F
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- Animals, Bufanolides metabolism, Calcium Channels drug effects, Cells, Cultured, Ganglia, Spinal cytology, Guinea Pigs, Myocardial Contraction drug effects, Myocardium cytology, Myocardium metabolism, Neurons drug effects, Neurons metabolism, Rats, Rats, Sprague-Dawley, Bufanolides pharmacology, Ganglia, Spinal drug effects, Heart Ventricles drug effects, Plants, Sodium-Potassium-Exchanging ATPase antagonists & inhibitors
- Abstract
The aim of the present study was to investigate the effects of neuro- (cumulative) and cardiotoxic (non-cumulative) bufadienolides originating from plants (phyto-bufadienolides) on the Na+/K+ pump current (Ip) in cardiac (rat and guinea pig) and dorsal root ganglion cells (guinea pig), and on Ca2+ currents in cardiomyocytes (guinea pig). All bufadienolides tested (non-cumulative drugs: thesiuside, tyledoside C; lanceotoxin B and tyledoside F for the neurotoxic group) were potent blockers of Ip at concentrations in the micro- and submicromolar range. K0.5 values for Ip inhibition in dorsal root ganglion neurones were slightly lower compared to cardiomyocytes, but the order of potency was similar in both cell types. Both classes of bufadienolides were equipotent in suppressing Ip, generated by high- and low-affinity pump isoforms. Phenomena related to pump inhibition, as hypercontracture and increase in T-type Ca2+ current in cardiomyocytes, were influenced to the same extent. Therefore, from these results, neurospecificity of some bufadienolides could not be explained by differences in Na+/K+ pump affinity.
- Published
- 1997
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15. Preferential block of the veratridine-induced, non-inactivating Na+ current by R56865 in single cardiac Purkinje cells.
- Author
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Verdonck F, Bielen FV, and Ver Donck L
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- Animals, Benzothiazoles, Heart drug effects, In Vitro Techniques, Membrane Potentials drug effects, Myocardium cytology, Myocardium metabolism, Purkinje Cells drug effects, Rabbits, Tetrodotoxin pharmacology, Piperidines pharmacology, Purkinje Cells metabolism, Sodium Channels drug effects, Thiazoles pharmacology, Veratridine pharmacology
- Abstract
The effect of the cardioprotective agent R56865 on the veratridine (VTD)-modified sodium current was investigated in single rabbit cardiac Purkinje cells and ventricular myocytes. A steady, tetrodotoxin (TTX)-sensitive Na+ current (the non-inactivating Na+ current) was absent in most cells studied. In the presence of veratridine (15 x 10(-6) M) a non-inactivating Na+ current could be elicited at membrane potentials between -80 to +60 mV, with a maximum at about 0 mV. R56865 blocked this current effectively. The concentration for half maximal inhibition of the non-inactivating Na+ current was 2 x 10(-7) M. Blockade of this Na+ current by R56865 increased with depolarization. R56865 was much more effective in inhibiting the non-inactivating Na+ current than in inhibiting time-dependent Na+ currents elicited by short depolarizing pulses. The blocking effect of R56865 on the steady state influx of Na+ may contribute to cardioprotection in depolarized cells and in cells with modified Na+ channels as may occur during ischemia and reperfusion.
- Published
- 1991
- Full Text
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16. Electrophysiological effects of aprindine on isolated heart preparations.
- Author
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Verdonck F, Vereecke J, and Vleugels A
- Subjects
- Action Potentials drug effects, Aniline Compounds pharmacology, Animals, Anti-Arrhythmia Agents metabolism, Carbon Radioisotopes, Cats, Cattle, Diethylamines pharmacology, Dogs, Erythrocytes drug effects, Guinea Pigs, Heart Conduction System drug effects, Hemolysis drug effects, In Vitro Techniques, Indenes metabolism, Membrane Potentials drug effects, Microelectrodes, Myocardium metabolism, Neural Conduction drug effects, Osmolar Concentration, Refractory Period, Electrophysiological drug effects, Species Specificity, Time Factors, Anti-Arrhythmia Agents pharmacology, Heart drug effects, Indenes pharmacology
- Published
- 1974
- Full Text
- View/download PDF
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