scholarly journals Regulated expression of endothelin converting enzymes in glomerular endothelial cells.

1997 ◽  
Vol 8 (4) ◽  
pp. 580-585 ◽  
Author(s):  
K Uchida ◽  
S Uchida ◽  
K Nitta ◽  
W Yumura ◽  
H Nihei
Keyword(s):  
Endothelial Cells ◽  
Protein Kinase C ◽  
Protein Kinase ◽  
Transcriptional Activation ◽  
Mrna Stability ◽  
Ribonuclease Protection Assay ◽  
Signaling Systems ◽  
Control Value ◽  
Kinase C ◽  
Glomerular Endothelial Cells

Endothelin converting enzyme (ECE) constitutes a potential regulatory site for the production of active mature endothelins. Two cDNAs (ECE-1 and -2) encoding ECE have recently been cloned, but the regulation of the expression of these ECE has not been clarified. In the study presented here, an attempt was made to determine whether or not glomerular endothelial cells (GEN) express ECE-1 and -2, and to learn how the expression of ECE-1 and -2 is regulated by kinase-mediated signaling systems. Ribonuclease protection assay revealed the expression of ECE-1 and -2 in cultured GEN, and the expression was increased approximately 2.5- and approximately 1.8-fold, respectively, by treatment with 10(-7) M 12-O-tetradecanocyl-phorbol-13-acetate (TPA) for 4 hours. These increases in ECE-1 and -2 expression with TPA were inhibited by cotreatment with calphostin C (10(-7) M). In contrast, 24-h treatment with 10(-7) M TPA significantly decreased the expression of ECE-1 and -2, indicating that the expression was tightly regulated by protein kinase C (PKC)-dependent mechanism(s). Actinomycin D (1 microgram/mL) abolished the TPA-induced increase of ECE-1 and -2 mRNA, whereas TPA treatment did not affect the mRNA stability of ECE-1 and -2, thus suggesting that TPA-induced increases of ECE-1 and -2 mRNA resulted from the transcriptional activation of ECE-1 and -2, gene, rather than from the increase of mRNA stability. In addition to the regulation by PKC, the effects of protein kinase A and G on ECE-1 and -2 expression were also examined. Treatment with chlorophenyl-thio cyclic AMP (200 microM) for 24 h decreased ECE-1 and -2 expression to approximately 50% and approximately 40% of the control value, respectively. 8-bromo-3', 5'-cyclic GMP also decreased ECE-1 and -2 expression to approximately 80% and approximately 25% of the control value, respectively. These results demonstrate that the expression of ECE-1 and -2 is regulated by kinase-mediated signaling systems, with the most prominent regulatory effect shown by protein kinase C.

scholarly journals Heparin down-regulates the phorbol ester-induced protein kinase C gene expression in human endothelial cells: enzyme-mediated autoregulation of protein kinase C-α and -δ genes1

FEBS Letters ◽  
1999 ◽  
Vol 449 (2-3) ◽  
pp. 135-140 ◽  
Author(s):  
Gianfranco Pintus ◽  
Bruna Tadolini ◽  
Margherita Maioli ◽  
Anna M. Posadino ◽  
Leonardo Gaspa ◽  
...  
Keyword(s):  
Gene Expression ◽  
Endothelial Cells ◽  
Protein Kinase C ◽  
Protein Kinase ◽  
Phorbol Ester ◽  
Human Endothelial Cells ◽  
Kinase C

Protein Kinase C Is Required for Long-Lasting Synaptic Enhancement by the Neuropeptide DRNFLRFamide in Crayfish

1998 ◽  
Vol 79 (2) ◽  
pp. 1127-1131 ◽  
Author(s):  
Rainer W. Friedrich ◽  
G. F. Molnar ◽  
Michael Schiebe ◽  
A. Joffre Mercier
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Intracellular Signaling ◽  
Neuromuscular Junctions ◽  
Initial Increase ◽  
Excitatory Postsynaptic Potential ◽  
Signaling Systems ◽  
Synaptic Modulation ◽  
Kinase C ◽  
Extensor Muscles

Friedrich, Rainer W., G. F. Molnar, Michael Schiebe, and A. Joffre Mercier. Protein kinase C is required for long-lasting synaptic enhancement by the neuropeptide DRNFLRFamide in crayfish. J. Neurophysiol. 79: 1127–1131, 1998. The FMRFamide-related neuropeptide AspArgAsnPheLeuArgPhe-NH2 (DRNFLRFamide, DF2) induces a long-lasting enhancement of synaptic transmission at neuromuscular junctions on the crayfish deep abdominal extensor muscles. Here we investigated the function of protein kinase C (PKC) in this effect because PKC has been implied in the control of long-term synaptic modulation in other systems. The general kinase antagonist staurosporine reduced both the initial increase in excitatory postsynaptic potential (EPSP) amplitude and the duration of synaptic enhancement. Unlike staurosporine, the selective PKC inhibitors, chelerythrine and bisindolylmaleimide, augmented the initial EPSP increase. However, like staurosporine, they also reduced the duration of synaptic enhancement. The PKC activator, phorbol-12-myristate 13-acetate, induced a long-lasting synaptic enhancement that was blocked by chelerythrine. These results show that synaptic enhancement by DF2 is mediated by different intracellular signaling systems that act in temporal sequence. The initial increase in EPSP amplitudes is negatively regulated by PKC and involves another, staurosporine-sensitive, kinase; whereas, the maintenance of synaptic enhancement requires PKC.

scholarly journals The expression of COX-2 in VEGF-treated endothelial cells is mediated through protein tyrosine kinase

2002 ◽  
Vol 11 (1) ◽  
pp. 17-22 ◽  
Author(s):  
Pravit Akarasereenont ◽  
Kitirat Techatraisak ◽  
Athiwat Thaworn ◽  
Sirikul Chotewuttakorn
Keyword(s):  
Endothelial Cells ◽  
Protein Kinase C ◽  
Protein Kinase ◽  
Tyrosine Kinase ◽  
Protein Tyrosine Kinase ◽  
Kinase Inhibitor ◽  
Kinase C ◽  
Protein Kinase C Inhibitor ◽  
Cox 2 ◽  
Cox 1

Cyclooxygenase (COX), existing as the COX-1 and COX-2 isoforms, converts arachidonic acid to prostaglandin H2, which is then further metabolized to various prostaglandins. Vascular endothelial growth factor (VEGF) has been shown to play important roles in inflammation and is upregulated by the prostaglandin E series through COX-2 in several cell types. Here, we have investigated the effects of VEGF on the COX isoform expressed in human umbilical vein endothelial cells (HUVEC). The signalling mechanism of the COX isoform expressed in endothelial cells activated with VEGF will be also investigated using the tyrosine kinase inhibitor, genistein, and protein kinase C inhibitor, staurosporine. The activity of COX2 was assessed by measuring the production of 6-keto-prostaglandin F1α in the presence of exogenous arachidonic acids (10 μM, 10 min) by enzyme immunoassay. The expression of COX isoform protein was detected by immunoblot using specific antibodies. Untreated HUVEC contained no COX-2 protein. In HUVEC treated with VEGF (0.01-50 ng/ml), COX-2 protein, but not COX-1, and COX activity were increased in a dose-dependent manner. Interestingly, the increased COX-2 protein and activity in response to VEGF (10 ng/ml) was inhibited by the tyrosine kinase inhibitor, genistein (0.05-5 μg/ml), but not by the protein kinase C inhibitor, staurosporine (0.1-10 ng/ml). Thus, the induction of COX-2 by VEGF in endothelial cells was mediated through protein tyrosine kinase, and the uses of specific COX-2 inhibitors in these conditions, in which VEGF was involved, might have a role.

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