The influence of septal lesions on sodium and water retention induced by Walker 256 tumor
Autor(a) principal: | |
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Data de Publicação: | 1999 |
Outros Autores: | , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Brazilian Journal of Medical and Biological Research |
Texto Completo: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1999000300010 |
Resumo: | In the course of studies on the effects of septal area lesions on neuroimmunomodulation and Walker 256 tumor development, it was observed that tumor-induced sodium and water retention was less marked in lesioned than in non-lesioned rats. In the present study possible mechanisms involved in this phenomenon were investigated. The experiments were performed in septal-lesioned (LW; N = 15) and sham-operated (SW; N = 7) 8-week-old male Wistar rats, which received multifocal simultaneous subcutaneous (sc) inoculations of Walker 256 tumor cells about 30 days after the stereotaxic surgery. Control groups (no tumor, sham-operated food-restricted (SFR), N = 7) and lesioned food-restricted (LFR, N = 10) were subjected to a feeding pattern similar to that observed in tumor-bearing animals. Multifocal inoculation of Walker 256 tumor rapidly induces anorexia, which is paradoxically accompanied by an increase in body weight, as a result of renal Na+ and fluid retention. These effects of the tumor were also seen in LW rats, although the rise in fractional sodium balance during the early clinical period was significantly smaller than in SW rats (day 4: SW = 47.6 ± 6.4% and LW = 13.8 ± 5.2%; day 5: SW = 57.5 ± 3.5% and LW = 25.7 ± 4.8%; day 6: SW = 54.4 ± 3.8% and LW = 32.1 ± 4.4%; P<0.05), suggesting a temporary reduction in tumor-induced sodium retention. In contrast, urine output was significantly reduced in SW rats and increased in LW rats (LW up to -0.85 and SW up to 4.5 ml/100 g body weight), with no change in osmolar excretion. These temporary changes in the tumor's effects on LW rats may reflect a "reversal" of the secondary central antidiuretic response induced by the tumor (from antidiuretic to diuretic). |
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Brazilian Journal of Medical and Biological Research |
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The influence of septal lesions on sodium and water retention induced by Walker 256 tumorNa+ retentionsecondary diuretic responsetumor systemic effectsseptal area lesionmultifocal tumor inoculationWalker 256 tumorIn the course of studies on the effects of septal area lesions on neuroimmunomodulation and Walker 256 tumor development, it was observed that tumor-induced sodium and water retention was less marked in lesioned than in non-lesioned rats. In the present study possible mechanisms involved in this phenomenon were investigated. The experiments were performed in septal-lesioned (LW; N = 15) and sham-operated (SW; N = 7) 8-week-old male Wistar rats, which received multifocal simultaneous subcutaneous (sc) inoculations of Walker 256 tumor cells about 30 days after the stereotaxic surgery. Control groups (no tumor, sham-operated food-restricted (SFR), N = 7) and lesioned food-restricted (LFR, N = 10) were subjected to a feeding pattern similar to that observed in tumor-bearing animals. Multifocal inoculation of Walker 256 tumor rapidly induces anorexia, which is paradoxically accompanied by an increase in body weight, as a result of renal Na+ and fluid retention. These effects of the tumor were also seen in LW rats, although the rise in fractional sodium balance during the early clinical period was significantly smaller than in SW rats (day 4: SW = 47.6 ± 6.4% and LW = 13.8 ± 5.2%; day 5: SW = 57.5 ± 3.5% and LW = 25.7 ± 4.8%; day 6: SW = 54.4 ± 3.8% and LW = 32.1 ± 4.4%; P<0.05), suggesting a temporary reduction in tumor-induced sodium retention. In contrast, urine output was significantly reduced in SW rats and increased in LW rats (LW up to -0.85 and SW up to 4.5 ml/100 g body weight), with no change in osmolar excretion. These temporary changes in the tumor's effects on LW rats may reflect a "reversal" of the secondary central antidiuretic response induced by the tumor (from antidiuretic to diuretic).Associação Brasileira de Divulgação Científica1999-03-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1999000300010Brazilian Journal of Medical and Biological Research v.32 n.3 1999reponame:Brazilian Journal of Medical and Biological Researchinstname:Associação Brasileira de Divulgação Científica (ABDC)instacron:ABDC10.1590/S0100-879X1999000300010info:eu-repo/semantics/openAccessGuimarães,F.Rettori,O.Vieira-Matos,A.N.Fernandes,G.A.eng1999-03-17T00:00:00Zoai:scielo:S0100-879X1999000300010Revistahttps://www.bjournal.org/https://old.scielo.br/oai/scielo-oai.phpbjournal@terra.com.br||bjournal@terra.com.br1414-431X0100-879Xopendoar:1999-03-17T00:00Brazilian Journal of Medical and Biological Research - Associação Brasileira de Divulgação Científica (ABDC)false |
dc.title.none.fl_str_mv |
The influence of septal lesions on sodium and water retention induced by Walker 256 tumor |
title |
The influence of septal lesions on sodium and water retention induced by Walker 256 tumor |
spellingShingle |
The influence of septal lesions on sodium and water retention induced by Walker 256 tumor Guimarães,F. Na+ retention secondary diuretic response tumor systemic effects septal area lesion multifocal tumor inoculation Walker 256 tumor |
title_short |
The influence of septal lesions on sodium and water retention induced by Walker 256 tumor |
title_full |
The influence of septal lesions on sodium and water retention induced by Walker 256 tumor |
title_fullStr |
The influence of septal lesions on sodium and water retention induced by Walker 256 tumor |
title_full_unstemmed |
The influence of septal lesions on sodium and water retention induced by Walker 256 tumor |
title_sort |
The influence of septal lesions on sodium and water retention induced by Walker 256 tumor |
author |
Guimarães,F. |
author_facet |
Guimarães,F. Rettori,O. Vieira-Matos,A.N. Fernandes,G.A. |
author_role |
author |
author2 |
Rettori,O. Vieira-Matos,A.N. Fernandes,G.A. |
author2_role |
author author author |
dc.contributor.author.fl_str_mv |
Guimarães,F. Rettori,O. Vieira-Matos,A.N. Fernandes,G.A. |
dc.subject.por.fl_str_mv |
Na+ retention secondary diuretic response tumor systemic effects septal area lesion multifocal tumor inoculation Walker 256 tumor |
topic |
Na+ retention secondary diuretic response tumor systemic effects septal area lesion multifocal tumor inoculation Walker 256 tumor |
description |
In the course of studies on the effects of septal area lesions on neuroimmunomodulation and Walker 256 tumor development, it was observed that tumor-induced sodium and water retention was less marked in lesioned than in non-lesioned rats. In the present study possible mechanisms involved in this phenomenon were investigated. The experiments were performed in septal-lesioned (LW; N = 15) and sham-operated (SW; N = 7) 8-week-old male Wistar rats, which received multifocal simultaneous subcutaneous (sc) inoculations of Walker 256 tumor cells about 30 days after the stereotaxic surgery. Control groups (no tumor, sham-operated food-restricted (SFR), N = 7) and lesioned food-restricted (LFR, N = 10) were subjected to a feeding pattern similar to that observed in tumor-bearing animals. Multifocal inoculation of Walker 256 tumor rapidly induces anorexia, which is paradoxically accompanied by an increase in body weight, as a result of renal Na+ and fluid retention. These effects of the tumor were also seen in LW rats, although the rise in fractional sodium balance during the early clinical period was significantly smaller than in SW rats (day 4: SW = 47.6 ± 6.4% and LW = 13.8 ± 5.2%; day 5: SW = 57.5 ± 3.5% and LW = 25.7 ± 4.8%; day 6: SW = 54.4 ± 3.8% and LW = 32.1 ± 4.4%; P<0.05), suggesting a temporary reduction in tumor-induced sodium retention. In contrast, urine output was significantly reduced in SW rats and increased in LW rats (LW up to -0.85 and SW up to 4.5 ml/100 g body weight), with no change in osmolar excretion. These temporary changes in the tumor's effects on LW rats may reflect a "reversal" of the secondary central antidiuretic response induced by the tumor (from antidiuretic to diuretic). |
publishDate |
1999 |
dc.date.none.fl_str_mv |
1999-03-01 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1999000300010 |
url |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1999000300010 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
10.1590/S0100-879X1999000300010 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
text/html |
dc.publisher.none.fl_str_mv |
Associação Brasileira de Divulgação Científica |
publisher.none.fl_str_mv |
Associação Brasileira de Divulgação Científica |
dc.source.none.fl_str_mv |
Brazilian Journal of Medical and Biological Research v.32 n.3 1999 reponame:Brazilian Journal of Medical and Biological Research instname:Associação Brasileira de Divulgação Científica (ABDC) instacron:ABDC |
instname_str |
Associação Brasileira de Divulgação Científica (ABDC) |
instacron_str |
ABDC |
institution |
ABDC |
reponame_str |
Brazilian Journal of Medical and Biological Research |
collection |
Brazilian Journal of Medical and Biological Research |
repository.name.fl_str_mv |
Brazilian Journal of Medical and Biological Research - Associação Brasileira de Divulgação Científica (ABDC) |
repository.mail.fl_str_mv |
bjournal@terra.com.br||bjournal@terra.com.br |
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1754302929686233088 |