scholarly journals Effect of secretagogues on chromogranin A synthesis in bovine cultured chromaffin cells. Possible regulation by protein kinase C

1989 ◽  
Vol 260 (3) ◽  
pp. 915-922 ◽  
Author(s):  
J P Simon ◽  
M F Bader ◽  
D Aunis
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Chromogranin A ◽  
Chromaffin Cells ◽  
Cell Types ◽  
Term Treatment ◽  
Synthesis Rate ◽  
Kinase C ◽  
Long Term Treatment ◽  
Bovine Chromaffin Cells

Chromogranin A is a major component of storage granules in many different secretory cell types. After [35S]methionine labelling of proteins from cultured bovine chromaffin cells, chromogranin A was immunoprecipitated with specific antibodies, and the radioactivity incorporated into chromogranin A was determined and used as an index of its synthesis rate. Depolarization of cells with nicotine or high K+ evoked a Ca2+-dependent increase in chromogranin A synthesis, whereas muscarine, which does not evoke significant Ca2+ influx from bovine chromaffin cells, had no effect on chromogranin A synthesis. Forskolin, an activator of adenylate cyclase, affected neither the basal nor the nicotine-stimulated rate of chromogranin A synthesis. In contrast, 12-O-tetradecanoylphorbol 13-acetate (TPA), an activator of protein kinase C, significantly enhanced the incorporation of radioactivity into chromogranin A. Sphingosine, an inhibitor of protein kinase C, abolished both nicotine-stimulated and TPA-induced chromogranin A synthesis. In addition, long-term treatment of chromaffin cells with TPA decreased protein kinase C activity and inhibited the nicotine-stimulated chromogranin A synthesis. These results suggest that protein kinase C may play an important role in the control of chromogranin A synthesis.

Intracellular mechanism of Pb(2+)-induced norepinephrine release from bovine chromaffin cells

1993 ◽  
Vol 265 (6) ◽  
pp. C1630-C1636 ◽  
Author(s):  
J. L. Tomsig ◽  
J. B. Suszkiw
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Chromaffin Cells ◽  
Kinase C ◽  
Dopamine Beta Hydroxylase ◽  
Intracellular Mechanism ◽  
Protein Kinase C Inhibitor ◽  
Bovine Chromaffin Cells ◽  
Free Metal ◽  
Analogous Mechanism

The intracellular mechanism of Pb(2+)-induced release of norepinephrine (NE) was investigated in comparison with Ca2+ in bovine chromaffin cells permeabilized with staphylococcal alpha-toxin. Pb2+ activated NE release at considerably lower concentrations [concentration of free metal giving half maximal metal-dependent release (K0.5) 4.6 nM] than Ca2+ (K0.5 2.4 microM). The release of NE was associated with the release of dopamine-beta-hydroxylase but not lactate dehydrogenase. The maximal secretory responses produced by Pb2+ and Ca2+ were similar and nonadditive. Pb(2+)- and Ca(2+)-dependent releases showed a similar requirement for MgATP and were equally enhanced by protein kinase C activator 12-O-tetradecanoylphorbol 13-acetate (TPA) but not by kinase A activator 8-bromoadenosine 3',5'-cyclic monophosphate free base. The protein kinase C inhibitor staurosporine blocked the TPA-stimulated component of secretion but had no effect on the NE release in the absence of TPA. Calmidazolium, an inhibitor of calmodulin, inhibited the secretion evoked by both metals to similar extent. Agents interacting with microtubules (colchicine and vinblastine) or microfilaments (cytochalasin B and phalloidin) had no effect on secretion induced by either metal cation. These observations indicate that both Pb2+ and Ca2+ act at a common site and activate the exocytotic release of NE by an analogous mechanism.

Munc18-1 phosphorylation by protein kinase C potentiates vesicle pool replenishment in bovine chromaffin cells

Neuroscience ◽  
2006 ◽  
Vol 143 (2) ◽  
pp. 487-500 ◽  
Author(s):  
U. Nili ◽  
H. de Wit ◽  
A. Gulyas-Kovacs ◽  
R.F. Toonen ◽  
J.B. Sørensen ◽  
...  
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Chromaffin Cells ◽  
Kinase C ◽  
Bovine Chromaffin Cells ◽  
Vesicle Pool

scholarly journals Differential down-regulation of protein kinase C selectively affects IgE-dependent exocytosis and inositol trisphosphate formation

1990 ◽  
Vol 270 (3) ◽  
pp. 679-684 ◽  
Author(s):  
G Gat-Yablonski ◽  
R Sagi-Eisenberg
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Inositol Phosphates ◽  
Inositol Phosphate ◽  
Term Treatment ◽  
Short Term Treatment ◽  
Kinase C ◽  
Serotonin Secretion ◽  
Long Term Treatment ◽  
Ic50 Values

Short-term treatment of rat basophilic leukaemia (RBL-2H3) cells with the phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA) activates protein kinase C (PKC) and results in the inhibition of the IgE-dependent formation of inositol phosphates, but in the potentiation of serotonin secretion. Long-term treatment with TPA, which depletes the cells of their endogenous PKC, eliminates both Ca2(+)-ionophore- and TPA- as well as IgE-dependent secretion, but it potentiates by 1.7-fold IgE-induced inositol phosphate formation. Taken together, these observations strongly suggest that the dual actions of TPA on IgE-dependent responses are both mediated by PKC. The opposing effects of TPA are differentially down-regulated. Following TPA treatment, the rate by which the cells lose their ability to undergo exocytosis is faster than the rate at which inhibition of inositol phosphates formation is relieved and their production potentiated. In addition, both processes show different sensitivities to inhibitors of PKC action. Whereas IgE-dependent secretion is completely blocked by the PKC inhibitors K252a, H-7 and sphingosine [concns. causing 50% inhibition (IC50 values) = 25 ng/ml 80 microns and 30 microns respectively], these inhibitors do not relieve inhibition of inositol phosphate formation by TPA, nor do they potentiate this response. These results may imply that the bidirectional control exerted by PKC on IgE-dependent responses is mediated by its different isoenzymes.

The role of protein kinase C in nicotinic responses of bovine chromaffin cells

1996 ◽  
Vol 311 (1) ◽  
pp. 87-94 ◽  
Author(s):  
Kylie Loneragan ◽  
Tat B. Cheah ◽  
Stephen J. Bunn ◽  
Philip D. Marley
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Chromaffin Cells ◽  
Kinase C ◽  
Bovine Chromaffin Cells

Protein kinase C-α and the regulation of diverse cell responses

2017 ◽  
Vol 8 (3-4) ◽  
pp. 143-153 ◽  
Author(s):  
Rishi Kant Singh ◽  
Sanjay Kumar ◽  
Pramod Kumar Gautam ◽  
Munendra Singh Tomar ◽  
Praveen Kumar Verma ◽  
...  
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Cellular Localization ◽  
Cellular Transformation ◽  
Cell Types ◽  
Adapter Proteins ◽  
Cellular Functions ◽  
Cell Responses ◽  
Kinase C ◽  
Cellular Compartments

AbstractProtein kinase C (PKC) comprises a family of lipid-sensitive enzymes that have been involved in a broad range of cellular functions. PKC-α is a member of classical PKC with ubiquitous expression and different cellular localization. This unique PKC isoform is activated by various signals which evoke lipid hydrolysis, after activation it interacts with various adapter proteins and is localized to specific cellular compartments where it is devised to work. The universal expression and activation by various stimuli make it a perfect player in uncountable cellular functions including differentiation, proliferation, apoptosis, cellular transformation, motility, adhesion and so on. However, these functions are not intrinsic properties of PKC-α, but depend on cell types and conditions. The activities of PKC-α are managed by the various pharmacological activators/inhibitors and antisense oligonucleotides. The aim of this review is to elaborate the structural feature, and provide an insight into the mechanism of PKC-α activation and regulation of its key biological functions in different cellular compartments to develop an effective pharmacological approach to regulate the PKC-α signal array.

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