Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
1999-10-19
pubmed:abstractText
The insulin response to the sulfonylurea glibenclamide was markedly impaired in pancreatic beta-cell line MIN6 cells with chronic glibenclamide treatment (MIN6-Glib). The intracellular calcium concentration increased only slightly in response to glibenclamide in MIN6-Glib. While the properties of the voltage-dependent calcium channels were not altered, the conductance of the K(ATP) channels, the primary target of glibenclamide, was significantly reduced in MIN6-Glib. The ATP-sensitive K+ (K(ATP)) channels in MIN6 cells comprise inwardly rectifying K+ channel member Kir6.2 subunits and sulfonylurea receptor (SUR) 1 subunits. MIN6 cells have both high- and low-affinity binding sites for glibenclamide. The binding affinities at these two sites were unchanged, but the maximum binding capacities at both sites were similarly increased by chronic glibenclamide treatment. Both SUR1 and Kir6.2 mRNA levels were not altered, but SUR1 protein was rather increased in MIN6-Glib. In addition, electron microscopic examination revealed a majority of the SUR1 to be present in a cluster near the plasma membrane in control MIN6, while it tends to be distributed in the cytoplasm in MIN6-Glib. These data suggest that chronic glibenclamide treatment causes the defect in acute glibenclamide-induced insulin secretion by reducing the number of functional K(ATP) channels on the plasma membrane of the beta-cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0012-1797
pubmed:author
pubmed:issnType
Print
pubmed:volume
48
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2001-6
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Unresponsiveness to glibenclamide during chronic treatment induced by reduction of ATP-sensitive K+ channel activity.
pubmed:affiliation
Department of Molecular Medicine, Chiba University Graduate School of Medicine, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't