Stimulation of 90- and 70-kDa ribosomal protein S6 kinases by arginine vasopressin and lysophosphatidic acid in rat cardiomyocytes
| Autor: | Sidney Katz, Steven L. Pelech, Duan-Fang Liao, Sung Ouk Kim, Yan-Jun Xu |
|---|---|
| Rok vydání: | 2000 |
| Předmět: |
Male
MAPK/ERK pathway endocrine system P70-S6 Kinase 1 In Vitro Techniques Biology Biochemistry Rats Sprague-Dawley Phosphatidylinositol 3-Kinases chemistry.chemical_compound Lysophosphatidic acid Animals Protein kinase A Protein kinase C Mitogen-Activated Protein Kinase 1 Pharmacology Mitogen-Activated Protein Kinase 3 Kinase Myocardium Ribosomal Protein S6 Kinases Heart Molecular biology Rats Arginine Vasopressin Enzyme Activation Molecular Weight chemistry Ribosomal protein s6 Mitogen-activated protein kinase biology.protein lipids (amino acids peptides and proteins) Lysophospholipids Mitogen-Activated Protein Kinases biological phenomena cell phenomena and immunity hormones hormone substitutes and hormone antagonists |
| Zdroj: | Biochemical Pharmacology. 59:1163-1171 |
| ISSN: | 0006-2952 |
| Popis: | Arginine vasopressin (AVP) and lysophosphatidic acid (LPA) have been shown to stimulate protein kinase C (PKC) and mitogen-activated protein (MAP) kinases and the proliferation of vascular smooth muscle cells. However, the actions of these two agents in cardiomyocytes are less well understood. To investigate the signal transduction pathways of AVP and LPA, freshly isolated adult rat cardiomyocytes were examined. Both AVP and LPA induced concentration- and time-dependent stimulation of the phosphotransferase activities of p90 ribosomal S6 kinases (RSK) and their upstream activators, extracellularly regulated kinases (ERK) 1 and 2. The activation of ERK1 and ERK2 by LPA was PKC- and phosphatidylinositol 3-kinase (PI 3-kinase)-dependent. However, AVP-induced activation of RSK2, a downstream substrate of ERK1 and ERK2, was PKC-dependent and PI 3-kinase-independent. AVP and LPA were also observed to increase the phosphotransferase activity of p70 ribosomal protein S6 kinase (p70 S6K) in a time- and concentration-dependent manner. The activation of p70 S6K by LPA and AVP was PI 3-kinase-dependent. PKC was necessary in AVP- but not in LPA-induced activation of p70 S6K. Since RSK and p70 S6K have been implicated in the regulation of translational control of protein synthesis, we concluded that AVP and LPA may stimulate the growth of cardiomyocytes through these two protein kinase cascades. |
| Databáze: | OpenAIRE |
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