Linked Life Data

2990873

Source:http://linkedlifedata.com/resource/pubmed/id/2990873

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1985-9-19
pubmed:abstractText
To assess whether islet cells are equipped with recognition units which allow an intra-islet regulation via released hormones, the presence of insulin and glucagon receptors is investigated on purified pancreatic A and B cells. Mono-[125I]glucagon is shown to bind specifically to islet B cells, with similar binding characteristics as in isolated hepatocytes but involving less receptors per cell (2.10(4) per B cell vs. 8.10(5) per liver cell). Binding is half-maximally displaced by 5.10(-9) M glucagon, a concentration known to induce half-maximal biological effects in isolated B cells. These results are compatible with a regulatory role of glucagon in the insulin release process. No specific binding of [125I]tyr-A14-insulin is detected on pancreatic A cells. In order to increase receptor assay sensitivity, [123I]tyr-A14-insulin is prepared with at least 5-fold higher specific activity. Its validity for in vitro receptor analysis is demonstrated in IM-9 lymphocytes, where insulin binding is detectable down to 10(4) cells/ml. However, no insulin-binding sites are identified on pancreatic A cells, even at 10(6) cells/ml. If isolated A cells contain high affinity insulin receptors, their number should be inferior to 400 per cell, which is 50- to 500-fold lower than in classical insulin target cells. These findings explain the insensitivity of the glucagon release process to acute exposure to insulin.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0013-7227
pubmed:author
pubmed:issnType
Print
pubmed:volume
117
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
841-8
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Pancreatic hormone receptors on islet cells.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't