Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2002-11-6
pubmed:abstractText
We previously reported that erythropoietin (Epo) has a mitogenic effect on rat vascular smooth muscle cells (VSMC) and that activation of the mitogen-activated protein kinase (MAPK) cascade is an important mediator for Epo-induced mitogenesis. An increase in intracellular cAMP has an antiproliferative effect on VSMC. We therefore hypothesized that cAMP effectors inhibit Epo-induced MAPK activation in rat VSMC. When we exposed VSMC to recombinant human Epo (rHuEpo), DNA synthesis was increased. Forskolin (Fsk) or cilostazol (Cil) decreased the DNA synthesis stimulated by rHuEpo. Coincubation with Rp-cAMPS triethylamine canceled the suppression of DNA synthesis and MAPK activity by Fsk. Both rHuEpo and phorbol 12-myristate 13-acetate upregulated phosphorylations of MEK and MAPK. Pretreatment with Fsk inhibited these phosphorylations. Protein kinase C inhibitors also suppressed MEK and MAPK phosphorylations. Moreover, Fsk induced phosphorylation of Raf-1 at serine-259. These results indicated that cAMP inhibited Epo-induced MAPK activation and that this suppression might be regulated upstream or at Raf-1. The results also suggested that these agents, which could accumulate cAMP, might be protective for Epo-stimulated direct action.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0363-6143
pubmed:author
pubmed:issnType
Print
pubmed:volume
283
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
C1715-21
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:12419709-Animals, pubmed-meshheading:12419709-Cell Division, pubmed-meshheading:12419709-Cell Survival, pubmed-meshheading:12419709-Cyclic AMP, pubmed-meshheading:12419709-Drug Synergism, pubmed-meshheading:12419709-Enzyme Activation, pubmed-meshheading:12419709-Erythropoietin, pubmed-meshheading:12419709-Forskolin, pubmed-meshheading:12419709-Male, pubmed-meshheading:12419709-Mitogen-Activated Protein Kinase Kinases, pubmed-meshheading:12419709-Mitogen-Activated Protein Kinases, pubmed-meshheading:12419709-Muscle, Smooth, Vascular, pubmed-meshheading:12419709-Phosphorylation, pubmed-meshheading:12419709-Protein Kinase C, pubmed-meshheading:12419709-Proto-Oncogene Proteins c-raf, pubmed-meshheading:12419709-Rats, pubmed-meshheading:12419709-Rats, Sprague-Dawley, pubmed-meshheading:12419709-Recombinant Proteins, pubmed-meshheading:12419709-Thionucleotides
pubmed:year
2002
pubmed:articleTitle
Modulation of the erythropoietin-induced proliferative pathway by cAMP in vascular smooth muscle cells.
pubmed:affiliation
Division of Nephrology, Department of Internal Medicine, Jichi Medical School, Tochigi 329-0498, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't