Linked Life Data

3597411

Source:http://linkedlifedata.com/resource/pubmed/id/3597411

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
19
pubmed:dateCreated
1987-8-14
pubmed:abstractText
Phorbol esters have been shown to cause degradation and synthesis of phosphatidylcholine. The present studies measure effects of another class of protein kinase C activators, the 1,2-diacylglycerols, on phosphatidylcholine metabolism using GH3 rat pituitary cells. 1,2-Dioctanoylglycerol (diC8, 200 micrograms/ml) reduced phosphatidylcholine levels to 95 and 70% of control by 5 min and 1 h, respectively, in cells labeled to equilibrium with [3H]choline. Concomitantly, lysophosphatidylcholine increased 3.5-fold by 15 min and remained elevated for 1 h. Glycerol 3-phosphocholine, the product of sequential deacylation of phosphatidylcholine, increased 5-fold in the medium over 1 h. DiC8 also increased the levels of unesterified arachidonic and stearic acids. Arachidonic acid was preferentially released from the 2-position of phosphatidylcholine to form lysophosphatidylcholine. These results suggest that diC8 stimulates a phospholipase A2. 1-Oleoyl-2-acetylglycerol produced similar effects. In contrast, phorbol esters failed to enhance degradation in these cells. 1,2-Diacylglycerols and phorbol esters, however, stimulated phosphatidylcholine synthesis via the CDP-choline pathway. This was measured as concentration-dependent incorporation of 32Pi and [3H]choline into phosphatidylcholine in short-term labeling studies. The effects of maximal concentrations of diC8 and the phorbol ester, 12-O-tetradecanoylphorbol-13-acetate, were additive. Furthermore, in cells down-modulated for phorbol ester action, diC8-induced degradation and synthesis were unchanged. These studies demonstrate that phorbol esters and 1,2-diacylglycerols have different effects on phosphatidylcholine metabolism and suggest that 1,2-diacylglycerols may stimulate phosphatidylcholine metabolism via a pathway independent of the protein kinase C which mediates phorbol ester action. This represents the first description of a biochemical pathway activated by 1,2-diacylglycerols and not by phorbol esters.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
262
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
9204-10
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
1,2-Diacylglycerols and phorbol esters stimulate phosphatidylcholine metabolism in GH3 pituitary cells. Evidence for separate mechanisms of action.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.