Changes induced by glucose in the plasma membrane properties of pancreatic islets

Autores
Cortizo, Ana María; Paladini, A.; Díaz, G. B.; García, María Elisa; Gagliardino, Juan José
Año de publicación
1990
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
Partially purified membranes obtained from rat pancreatic isolated islets preincubated for 3 min with 3.3 and 16.6 mM glucose were labelled with 1,6-diphenyl-1,3,5-hexatriene to study fluorescence polarization. Other islets, incubated for 5 min with the same glucose concentration, were extracted and phospholipids separated by thin-layer chromatography. The composition of phospholipids of fatty acids was then studied by gas-liquid chromatography. Arrhenius plots of the microviscosity in membranes obtained from islets exhibited two components, a steeper slope below 18 degrees C and a gentler slope above 18 degrees C, indicating greater flow activation energy at temperatures below the transition point. Exposure of islets to 16.6 mM glucose significantly increased the flow activation energy (delta E), below and above the transition point. Islets incubated for 5 min with 16.6 mM glucose showed an increase in the percentage composition of 12:0 and 18:2 together with a decrease in the 20:2 W6 and 22:3 W3 fatty acids esterified to phospholipids. Regardless of these changes, no significant alterations occurred in the proportion of saturated fatty acids or in the double bond index; these measurements therefore did not account for the effects of glucose concentration in flow activation energy. The thermotropic changes reported here might be the consequence of some degree of disorder induced by glucose upon the membrane structure. This order alteration could either favor the membrane fusion which occurs during the emiocytosis or only reflects the consequence of such a process.
Facultad de Ciencias Médicas
Materia
Ciencias Médicas
Páncreas
Glucosa
pancreatic islet, B cell membrane, fatty acids lipid bilayer order, fluorescence polarization
Nivel de accesibilidad
acceso abierto
Condiciones de uso
http://creativecommons.org/licenses/by/4.0/
Repositorio
SEDICI (UNLP)
Institución
Universidad Nacional de La Plata
OAI Identificador
oai:sedici.unlp.edu.ar:10915/67400

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network_name_str SEDICI (UNLP)
spelling Changes induced by glucose in the plasma membrane properties of pancreatic isletsCortizo, Ana MaríaPaladini, A.Díaz, G. B.García, María ElisaGagliardino, Juan JoséCiencias MédicasPáncreasGlucosapancreatic islet, B cell membrane, fatty acids lipid bilayer order, fluorescence polarizationPartially purified membranes obtained from rat pancreatic isolated islets preincubated for 3 min with 3.3 and 16.6 mM glucose were labelled with 1,6-diphenyl-1,3,5-hexatriene to study fluorescence polarization. Other islets, incubated for 5 min with the same glucose concentration, were extracted and phospholipids separated by thin-layer chromatography. The composition of phospholipids of fatty acids was then studied by gas-liquid chromatography. Arrhenius plots of the microviscosity in membranes obtained from islets exhibited two components, a steeper slope below 18 degrees C and a gentler slope above 18 degrees C, indicating greater flow activation energy at temperatures below the transition point. Exposure of islets to 16.6 mM glucose significantly increased the flow activation energy (delta E), below and above the transition point. Islets incubated for 5 min with 16.6 mM glucose showed an increase in the percentage composition of 12:0 and 18:2 together with a decrease in the 20:2 W6 and 22:3 W3 fatty acids esterified to phospholipids. Regardless of these changes, no significant alterations occurred in the proportion of saturated fatty acids or in the double bond index; these measurements therefore did not account for the effects of glucose concentration in flow activation energy. The thermotropic changes reported here might be the consequence of some degree of disorder induced by glucose upon the membrane structure. This order alteration could either favor the membrane fusion which occurs during the emiocytosis or only reflects the consequence of such a process.Facultad de Ciencias Médicas1990info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdf49-54http://sedici.unlp.edu.ar/handle/10915/67400enginfo:eu-repo/semantics/altIdentifier/url/https://www.sciencedirect.com/science/article/pii/030372079090074Iinfo:eu-repo/semantics/altIdentifier/issn/0303-7207info:eu-repo/semantics/altIdentifier/hdl/11746/4498info:eu-repo/semantics/openAccesshttp://creativecommons.org/licenses/by/4.0/Creative Commons Attribution 4.0 International (CC BY 4.0)reponame:SEDICI (UNLP)instname:Universidad Nacional de La Platainstacron:UNLP2025-09-03T10:42:18Zoai:sedici.unlp.edu.ar:10915/67400Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-03 10:42:18.86SEDICI (UNLP) - Universidad Nacional de La Platafalse
dc.title.none.fl_str_mv Changes induced by glucose in the plasma membrane properties of pancreatic islets
title Changes induced by glucose in the plasma membrane properties of pancreatic islets
spellingShingle Changes induced by glucose in the plasma membrane properties of pancreatic islets
Cortizo, Ana María
Ciencias Médicas
Páncreas
Glucosa
pancreatic islet, B cell membrane, fatty acids lipid bilayer order, fluorescence polarization
title_short Changes induced by glucose in the plasma membrane properties of pancreatic islets
title_full Changes induced by glucose in the plasma membrane properties of pancreatic islets
title_fullStr Changes induced by glucose in the plasma membrane properties of pancreatic islets
title_full_unstemmed Changes induced by glucose in the plasma membrane properties of pancreatic islets
title_sort Changes induced by glucose in the plasma membrane properties of pancreatic islets
dc.creator.none.fl_str_mv Cortizo, Ana María
Paladini, A.
Díaz, G. B.
García, María Elisa
Gagliardino, Juan José
author Cortizo, Ana María
author_facet Cortizo, Ana María
Paladini, A.
Díaz, G. B.
García, María Elisa
Gagliardino, Juan José
author_role author
author2 Paladini, A.
Díaz, G. B.
García, María Elisa
Gagliardino, Juan José
author2_role author
author
author
author
dc.subject.none.fl_str_mv Ciencias Médicas
Páncreas
Glucosa
pancreatic islet, B cell membrane, fatty acids lipid bilayer order, fluorescence polarization
topic Ciencias Médicas
Páncreas
Glucosa
pancreatic islet, B cell membrane, fatty acids lipid bilayer order, fluorescence polarization
dc.description.none.fl_txt_mv Partially purified membranes obtained from rat pancreatic isolated islets preincubated for 3 min with 3.3 and 16.6 mM glucose were labelled with 1,6-diphenyl-1,3,5-hexatriene to study fluorescence polarization. Other islets, incubated for 5 min with the same glucose concentration, were extracted and phospholipids separated by thin-layer chromatography. The composition of phospholipids of fatty acids was then studied by gas-liquid chromatography. Arrhenius plots of the microviscosity in membranes obtained from islets exhibited two components, a steeper slope below 18 degrees C and a gentler slope above 18 degrees C, indicating greater flow activation energy at temperatures below the transition point. Exposure of islets to 16.6 mM glucose significantly increased the flow activation energy (delta E), below and above the transition point. Islets incubated for 5 min with 16.6 mM glucose showed an increase in the percentage composition of 12:0 and 18:2 together with a decrease in the 20:2 W6 and 22:3 W3 fatty acids esterified to phospholipids. Regardless of these changes, no significant alterations occurred in the proportion of saturated fatty acids or in the double bond index; these measurements therefore did not account for the effects of glucose concentration in flow activation energy. The thermotropic changes reported here might be the consequence of some degree of disorder induced by glucose upon the membrane structure. This order alteration could either favor the membrane fusion which occurs during the emiocytosis or only reflects the consequence of such a process.
Facultad de Ciencias Médicas
description Partially purified membranes obtained from rat pancreatic isolated islets preincubated for 3 min with 3.3 and 16.6 mM glucose were labelled with 1,6-diphenyl-1,3,5-hexatriene to study fluorescence polarization. Other islets, incubated for 5 min with the same glucose concentration, were extracted and phospholipids separated by thin-layer chromatography. The composition of phospholipids of fatty acids was then studied by gas-liquid chromatography. Arrhenius plots of the microviscosity in membranes obtained from islets exhibited two components, a steeper slope below 18 degrees C and a gentler slope above 18 degrees C, indicating greater flow activation energy at temperatures below the transition point. Exposure of islets to 16.6 mM glucose significantly increased the flow activation energy (delta E), below and above the transition point. Islets incubated for 5 min with 16.6 mM glucose showed an increase in the percentage composition of 12:0 and 18:2 together with a decrease in the 20:2 W6 and 22:3 W3 fatty acids esterified to phospholipids. Regardless of these changes, no significant alterations occurred in the proportion of saturated fatty acids or in the double bond index; these measurements therefore did not account for the effects of glucose concentration in flow activation energy. The thermotropic changes reported here might be the consequence of some degree of disorder induced by glucose upon the membrane structure. This order alteration could either favor the membrane fusion which occurs during the emiocytosis or only reflects the consequence of such a process.
publishDate 1990
dc.date.none.fl_str_mv 1990
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
Articulo
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://sedici.unlp.edu.ar/handle/10915/67400
url http://sedici.unlp.edu.ar/handle/10915/67400
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/url/https://www.sciencedirect.com/science/article/pii/030372079090074I
info:eu-repo/semantics/altIdentifier/issn/0303-7207
info:eu-repo/semantics/altIdentifier/hdl/11746/4498
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
Creative Commons Attribution 4.0 International (CC BY 4.0)
eu_rights_str_mv openAccess
rights_invalid_str_mv http://creativecommons.org/licenses/by/4.0/
Creative Commons Attribution 4.0 International (CC BY 4.0)
dc.format.none.fl_str_mv application/pdf
49-54
dc.source.none.fl_str_mv reponame:SEDICI (UNLP)
instname:Universidad Nacional de La Plata
instacron:UNLP
reponame_str SEDICI (UNLP)
collection SEDICI (UNLP)
instname_str Universidad Nacional de La Plata
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institution UNLP
repository.name.fl_str_mv SEDICI (UNLP) - Universidad Nacional de La Plata
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