Linked Life Data

1486937

Source:http://linkedlifedata.com/resource/pubmed/id/1486937

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1993-2-19
pubmed:abstractText
Thrombin at concentrations as low as 20 pM (0.002 U ml-1) was found to stimulate inositol phosphate levels in cultured human non-pigmented ciliary epithelial cells. Several other proteases, including trypsin and plasmin, had little or no effect, of several protease inhibitors tested, only those with specificity for thrombin blocked the effect. Studies with active site-blocked thrombin suggested that the esterolytic active site of thrombin is required for inositol phosphate stimulation, while gamma-thrombin, which has reduced binding affinity to fibrinogen also showed reduced effectiveness in stimulating inositol phosphates. In the presence of 10 mM LiCl, thrombin stimulated inositol monophosphate, inositol bisphosphate and inositol trisphosphate formation, with a prolonged rise of the first and transient early rises in the latter two species. Thrombin also elevated intracellular Ca2+ levels as measured with the fluorescent calcium probe, indo-1-AM. This elevation could be blocked by prior addition to cells of the thrombin inhibitor, hirudin, and was dependent upon extracellular Ca2+ for the maintenance of an elevated level in the presence of thrombin. Incorporation of thymidine into DNA in confluent cultures was also stimulated by thrombin, with a four-fold increase in incorporation at 35 hr in thrombin-treated cells compared to controls. The half-maximal concentration for this process was 0.25 U ml-1. Pretreatment with 100 ng ml-1 pertussis toxin greatly reduced the thrombin effect, which is consistent with a role for a G-protein in stimulation of DNA synthesis by thrombin.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0014-4835
pubmed:author
pubmed:issnType
Print
pubmed:volume
55
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
785-95
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Thrombin stimulates inositol phosphate formation, intracellular calcium fluxes and DNA synthesis in cultured fetal human non-pigmented ciliary epithelial cells.
pubmed:affiliation
Department of Ophthalmology, University of California, San Francisco 94143-0730.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't