Linked Life Data

2905679

Source:http://linkedlifedata.com/resource/pubmed/id/2905679

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1989-3-6
pubmed:abstractText
The cellular mechanism by which the specific binding of [125I]insulin to intact rat adipocytes is inhibited by isoproterenol has been studied. By exposing control and isoproterenol-treated cells to trypsin (0-150 micrograms/ml for 20 min at 4 degrees C) and measuring the intact insulin receptor pool following detergent solubilization, a differential sensitivity to proteolysis of the cell membrane receptor was observed. At low trypsin concentration (less than 30 micrograms/ml), approximately 40% of the specific insulin binding in isoproterenol-treated cells was insensitive to proteolysis as compared to control cells. At higher levels of trypsin (50-150 micrograms/ml) both groups displayed similar levels of trypsin-insensitive receptors which, at the highest trypsin concentration, accounted for 10% of the total receptors in intact cells. Detergent-solubilized receptors from isoproterenol-treated cells, on the other hand, exhibited the same sensitivity to trypsin proteolysis as solubilized receptors from control cells. The time course of the onset and reversal of the isoproterenol-induced binding alteration in intact adipocytes has been analyzed by mild trypsinization (20 micrograms/ml). Results indicated that insulin receptors resistant to trypsin under these conditions mediated the decreased surface binding and were re-expressed on the cell surface upon removal of isoproterenol. Experiments in which adipocytes were fractionated into plasma membrane and Golgi-enriched fractions indicated that the loss of surface insulin binding was not accompanied by a decrease in the proportion of receptors in the adipocyte plasma membrane.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0303-7207
pubmed:author
pubmed:issnType
Print
pubmed:volume
60
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
87-94
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Differential sensitivity of the insulin receptor to proteolysis after beta-adrenergic stimulation.
pubmed:affiliation
Department of Anatomy, University of Iowa, Iowa City 52242.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't