Linked Life Data

2834407

Source:http://linkedlifedata.com/resource/pubmed/id/2834407

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1988-5-27
pubmed:abstractText
Previous studies have suggested that cyclic GMP and/or Ca2+ might function as second messengers in the induction by exogenous cyclic AMP of the cyclic AMP phosphodiesterase (PD) in Dictyostelium discoideum. To assess further the role of Ca2+ in PD induction we examined the effect on this process of a number of putative Ca2+-channel blockers. At relatively low micromolar concentrations, TMB-8, nicardipine, nifedipine, diltiazem and verapamil all altered cell shape and inhibited PD induction in a similar dose-dependent fashion. Concentrations of these drugs that abolished PD induction had no effect on cell viability; however, higher concentrations reduced viability and caused cell lysis. All effects of these compounds on the cells were antagonized at least partially by 5-10 mM-Ca2+. Other cations tested were considerably less effective. Like the organic inhibitors, La3+ also altered cell shape, inhibited PD induction and reduced cell viability at elevated concentrations, but its effect on the cells appeared to be more complex. Inhibition of PD induction by the organic antagonists could not be attributed solely to an impaired uptake of extracellular Ca2+, a reduction of ATP pools in the cells or a direct effect on calmodulin. Concentrations of TMB-8 that inhibited PD induction had little effect on the cyclic GMP response. Therefore, this compound did not inhibit PD induction indirectly by blocking cyclic GMP synthesis.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-9533
pubmed:author
pubmed:issnType
Print
pubmed:volume
88 ( Pt 3)
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
379-88
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Effects of calcium antagonists on cyclic AMP phosphodiesterase induction in Dictyostelium discoideum.
pubmed:affiliation
Department of Biology, York University, Ontario, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't