Cyclic AMP-Mediated Induction of the Cyclic AMP Phosphodiesterase of C-6 Glioma Cells
AUTOR(ES)
Schwartz, Joan P.
RESUMO
Long-term regulation of the cyclic nucleotide phosphodiesterase of the C-6 rat glioma cell line has been studied. Both the low Km and high Km activities can be induced by elevation of intracellular cyclic AMP levels following either dibutyryl cyclic AMP or norepinephrine treatment of the cells. The enzymes are maximally induced by 3-4 hr. The presence of either cycloheximide or actinomycin D prevents induction by either dibutyryl cyclic AMP or norepinephrine. Evidence is presented that the norepinephrine effect is mediated by the β-catecholamine receptor. The increased phosphodiesterase activity causes a partial refractoriness to a second challenge with norepinephrine, which can be overcome by blockade of the induction with cycloheximide. The results suggest that just as short-term regulation of cyclic AMP levels occurs via changes in the rates of synthesis or degradation, long-term alterations of the system may also involve either the adenylate cyclase or the phosphodiesterase.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=434280Documentos Relacionados
- Cyclic AMP-mediated induction of ornithine decarboxylase of glioma and neuroblastoma cells.
- Cell-specific cyclic AMP-mediated induction of the PDGF receptor.
- Interleukin-6- and Cyclic AMP-Mediated Signaling Potentiates Neuroendocrine Differentiation of LNCaP Prostate Tumor Cells
- Reversal of Cyclic AMP-Mediated Intestinal Secretion by Ethacrynic Acid
- Cyclic AMP-Mediated Inhibition of Cell Growth Requires the Small G Protein Rap1