Linked Life Data

207754

Source:http://linkedlifedata.com/resource/pubmed/id/207754

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1978-8-14
pubmed:abstractText
Epinephrine increased adenylate cyclase activity 10 to 15 fold in lysates of the cultured human astrocytoma cell line 132-1N1. GTP had little effect on adenylate cyclase activity of lysed cell preparations either with or without added epinephrine. However, the epinephrine stimulation of adenylate cyclase was essentially lost (less than 90%) when a washed nuclei-free membrane preparation of the cyclase was assayed. A 10 to 15 fold epinephrine stimulation of the membrane adenylate cyclase could be demonstrated if cytosol of GTP were added to the assay with the hormone. The criteria of anion exchange, cation exchange, gel exclusion and paper chromatography indicated that the cytosolic agents which acted synergistically with hormones were GTP and GDP. The apparent Kact's for the synergistic action of GDP and GTP were essentially identical (1.0 muM) and of all the other nucleotides examined only GDP had a potency similar to GTP. However, the effect of GDP was apparently due to its rapid conversion to GTP even in the absence of a regenerating system. With epinephrine pretreatment of the intact 132-1N1 cells there was a specific loss of epinephrine stimulation of adenylate cyclase activity. The hormone pretreatment did not alter the capacity of the cytosol from these desensitized cells to potentiate epinephrine stimulation of the cyclase. Rather, the alteration was in the particulate fraction of the lysate. The desensitization of the membranous cyclase was stable and not reversed by GTP.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0095-1544
pubmed:author
pubmed:issnType
Print
pubmed:volume
4
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
71-85
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1978
pubmed:articleTitle
Endogenous GTP and the regulation of epinephrine stimulation of adenylate cyclase.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S.