Protein kinase C epsilon-dependent extracellular signal-regulated kinase 5 phosphorylation and nuclear translocation involved in cardiomyocyte hypertrophy with angiotensin II stimulation

2009 ◽  
pp. n/a-n/a ◽  
Author(s):  
Zhuo Zhao ◽  
Wei Wang ◽  
Jing Geng ◽  
Liqi Wang ◽  
Guohai Su ◽  
...  
Keyword(s):  
Protein Kinase C ◽  
Angiotensin Ii ◽  
Protein Kinase ◽  
Nuclear Translocation ◽  
Cardiomyocyte Hypertrophy ◽  
Extracellular Signal Regulated Kinase ◽  
Kinase C ◽  
Protein Kinase C Epsilon ◽  
Extracellular Signal

Desflurane Preconditioning Induces Time-dependent Activation of Protein Kinase C Epsilon and Extracellular Signal-regulated Kinase 1 and 2 in the Rat Heart In Vivo 

2004 ◽  
Vol 101 (6) ◽  
pp. 1372-1380 ◽  
Author(s):  
Octavian Toma ◽  
Nina C. Weber ◽  
Jessica I. Wolter ◽  
Detlef Obal ◽  
Benedikt Preckel ◽  
...  
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Infarct Size ◽  
Time Dependent ◽  
Extracellular Signal Regulated Kinase ◽  
Calphostin C ◽  
Kinase C ◽  
Pkc Epsilon ◽  
Protein Kinase C Epsilon ◽  
Extracellular Signal

Background Activation of protein kinase C epsilon (PKC-epsilon) and extracellular signal-regulated kinase 1 and 2 (ERK1/2) are important for cardioprotection by preconditioning. The present study investigated the time dependency of PKC-epsilon and ERK1/2 activation during desflurane-induced preconditioning in the rat heart. Methods Anesthetized rats were subjected to regional myocardial ischemia and reperfusion, and infarct size was measured by triphenyltetrazoliumchloride staining (percentage of area at risk). In three groups, desflurane-induced preconditioning was induced by two 5-min periods of desflurane inhalation (1 minimal alveolar concentration), interspersed with two 10-min periods of washout. Three groups did not undergo desflurane-induced preconditioning. The rats received 0.9% saline, the PKC blocker calphostin C, or the ERK1/2 inhibitor PD98059 with or without desflurane preconditioning (each group, n = 7). Additional hearts were excised at four different time points with or without PKC or ERK1/2 blockade: without further treatment, after the first or the second period of desflurane-induced preconditioning, or at the end of the last washout phase (each time point, n = 4). Phosphorylated cytosolic PKC-epsilon and ERK1/2, and membrane translocation of PKC-epsilon were determined by Western blot analysis (average light intensity). Results Desflurane significantly reduced infarct size from 57.2 +/- 4.7% in controls to 35.2 +/- 16.7% (desflurane-induced preconditioning, mean +/- SD, P < 0.05). Both calphostin C and PD98059 abolished this effect (58.8 +/- 13.2% and 64.2 +/- 15.4% respectively, both P < 0.05 versus desflurane-induced preconditioning). Cytosolic phosphorylated PKC-epsilon reached its maximum after the second desflurane-induced preconditioning and returned to baseline after the last washout period. Both calphostin C and PD98059 inhibited PKC-epsilon activation. ERK1/2 phosphorylation reached its maximum after the first desflurane-induced preconditioning and returned to baseline after the last washout period. Calphostin C had no effect on ERK1/2 phosphorylation. Conclusions Both, PKC and ERK1/2 mediate desflurane-induced preconditioning. PKC-epsilon and ERK1/2 are both activated in a time dependent manner during desflurane-induced preconditioning, but ERK1/2 activation during desflurane-induced preconditioning is not PKC dependent. Moreover, ERK1/2 blockade abolished PKC-epsilon activation, suggesting ERK-dependent activation of PKC-epsilon during desflurane-induced preconditioning.

scholarly journals Adenylate cyclase, cyclic AMP and extracellular-signal-regulated kinase-2 in airway smooth muscle: modulation by protein kinase C and growth serum

1995 ◽  
Vol 306 (3) ◽  
pp. 723-726 ◽  
Author(s):  
N Moughal ◽  
P A Stevens ◽  
D Kong ◽  
S Pyne ◽  
N J Pyne
Keyword(s):  
Smooth Muscle ◽  
Protein Kinase C ◽  
Protein Kinase ◽  
Cyclic Amp ◽  
Adenylate Cyclase ◽  
Airway Smooth Muscle ◽  
Phospholipase D ◽  
Extracellular Signal Regulated Kinase ◽  
Kinase C ◽  
Extracellular Signal

Bradykinin and phorbol 12-myristate 13-acetate stimulate adenylate cyclase activity in serum-depleted cultured airway smooth muscle via a protein kinase C (PKC)-dependent pathway. The probable target is the type II adenylate cyclase, which can integrate coincident signals from both PKC and Gs. Therefore, activation of Gs (by cholera-toxin pre-treatment) amplified the bradykinin-stimulated cyclic AMP signal and concurrently attenuated the partial activation of extracellular-signal-regulated kinase-2 (ERK-2) by bradykinin. We have previously demonstrated that, in order to induce full activation of ERK-2 with bradykinin, it is necessary to obliterate PKC-stimulated cyclic AMP formation. We concluded that the cyclic AMP signal limits the magnitude of ERK-2 activation [Pyne, Moughal, Stevens, Tolan and Pyne (1994) Biochem. J. 304, 611-616]. The present study indicates that the bradykinin-stimulated ERK-2 pathway is entirely cyclic AMP-sensitive, and suggests that coincident signal detection by adenylate cyclase may be an important physiological route for the modulation of early mitogenic signalling. Furthermore, the direct inhibition of adenylate cyclase activity enables bradykinin to induce DNA synthesis, indicating that the PKC-dependent activation of adenylate cyclase limits entry of cells into the cell cycle. These studies suggest that the mitogenicity of an agonist may be governed, in part, by its ability to stimulate an inhibitory cyclic AMP signal pathway in the cell. The activation of adenylate cyclase by PKC appears to be downstream of phospholipase D. However, in cells that were maintained in growth serum (i.e. were not growth-arrested), bradykinin was unable to elicit a PKC-stimulated cyclic AMP response. The lesion in the signal-response coupling was not at the level of either the receptor or phospholipase D, which remain functionally operative and suggests modification occurs at either PKC or adenylate cyclase itself. These studies are discussed with respect to the cell signal regulation of mitogenesis in airway smooth muscle.

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