Stimulation of phosphatidylcholine hydrolysis in type II alveolar epithelial cells

1992 ◽  
Vol 263 (1) ◽  
pp. L42-L50
Author(s):  
L. C. Dubrovin ◽  
L. A. Brown
Keyword(s):  
Signal Transduction ◽  
Protein Kinase C ◽  
Protein Kinase ◽  
Alveolar Epithelial Cells ◽  
Type Ii ◽  
Alveolar Epithelial ◽  
Kinase C ◽  
Type Ii Pneumocytes ◽  
Stimulation Of ◽  
In Cells

The effects of phorbol 12-myristate 13-acetate (TPA) or ATP on phosphatidylcholine (PC) hydrolysis were investigated in cultured type II pneumocytes prelabeled with [3H]choline or 1-O-[3H]octadecyl-sn-glycero-3-phosphocholine ([3H]lyso-PAF). In cells prelabeled with [3H]choline, TPA or ATP stimulated an increase in [3H]choline, [3H]phosphocholine, and [3H]glycerophosphocholine. The formation of these choline metabolites was associated with a concomitant loss of [3H]PC but not from disaturated PC or phosphatidylinositol. In cells prelabeled with [3H]lyso-PAF, the formation of [3H]phosphatidic acid (PA) and then [3H]1,2-DG was stimulated by TPA or ATP and was associated with a loss of 3H from PC but not from disaturated PC or phosphatidylinositol. There was a concentration-dependent formation of [3H]1,2-DG and [3H]PA in response to ATP. Downregulation of protein kinase C with TPA abolished the stimulation of PC hydrolysis. In addition to the generation of metabolites indicative of phospholipase C and/or D activity, [3H]lyso-PC, a product of phospholipase A2, was also generated in response to TPA. These findings suggest an important role for PC breakdown in signal transduction in type II pneumocytes.

Pneumocystis Carinii β-glucan-induced Chemokine Secretion From Alveolar Epithelial Cells Requires Activation of Protein Kinase C and NF-κ

CHEST Journal ◽  
2003 ◽  
Vol 124 (4) ◽  
pp. 188S
Author(s):  
Scott E. Evans ◽  
Peter Y. Hahn ◽  
Frances M. Lebron-Ruiz ◽  
Theodore J. Kottom ◽  
Vishwajeet Puri ◽  
...  
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Epithelial Cells ◽  
Pneumocystis Carinii ◽  
Alveolar Epithelial Cells ◽  
Alveolar Epithelial ◽  
Kinase C

scholarly journals Dopamine-induced Exocytosis of Na,K-ATPase Is Dependent on Activation of Protein Kinase C-ε and -δ

2002 ◽  
Vol 13 (4) ◽  
pp. 1381-1389 ◽  
Author(s):  
Karen M. Ridge ◽  
Laura Dada ◽  
Emilia Lecuona ◽  
Alejandro M. Bertorello ◽  
Adrian I. Katz ◽  
...  
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Atpase Activity ◽  
Basolateral Membrane ◽  
Specific Inhibitor ◽  
Alveolar Epithelial Cells ◽  
Protein Abundance ◽  
Alveolar Epithelial ◽  
Kinase C ◽  
Late Endosomes

The purpose of this study was to define mechanisms by which dopamine (DA) regulates the Na,K-ATPase in alveolar epithelial type 2 (AT2) cells. The Na,K-ATPase activity increased by twofold in cells incubated with either 1 μM DA or a dopaminergic D1agonist, fenoldopam, but not with the dopaminergic D2agonist quinpirole. The increase in activity paralleled an increase in Na,K-ATPase α1 and β1 protein abundance in the basolateral membrane (BLM) of AT2 cells. This increase in protein abundance was mediated by the exocytosis of Na,K-pumps from late endosomal compartments into the BLM. Down-regulation of diacylglycerol-sensitive types of protein kinase C (PKC) by pretreatment with phorbol 12-myristate 13-acetate or inhibition with bisindolylmaleimide prevented the DA-mediated increase in Na,K-ATPase activity and exocytosis of Na,K-pumps to the BLM. Preincubation of AT2 cells with either 2-[1-(3-dimethylaminopropyl)-5-methoxyindol-3-yl]-3-(1H-indol-3-yl)maleimide (Gö6983), a selective inhibitor of PKC-δ, or isozyme-specific inhibitor peptides for PKC-δ or PKC-ε inhibited the DA-mediated increase in Na,K-ATPase. PKC-δ and PKC-ε, but not PKC-α or -β, translocated from the cytosol to the membrane fraction after exposure to DA. PKC-δ– and PKC-ε–specific peptide agonists increased Na,K-ATPase protein abundance in the BLM. Accordingly, dopamine increased Na,K-ATPase activity in alveolar epithelial cells through the exocytosis of Na,K-pumps from late endosomes into the basolateral membrane in a mechanism-dependent activation of the novel protein kinase C isozymes PKC-δ and PKC-ε.

Stimulation of surfactant lipid secretion from fetal type II pneumocytes by gastrin-releasing peptide

1996 ◽  
Vol 270 (3) ◽  
pp. L331-L337 ◽  
Author(s):  
N. Asokananthan ◽  
M. H. Cake
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Maximal Response ◽  
Type Ii ◽  
Dependent Protein Kinase ◽  
Gastrin Releasing Peptide ◽  
Camp Dependent Protein Kinase ◽  
Kinase C ◽  
Type Ii Pneumocytes ◽  
Dependent Protein

Gastrin-releasing peptide (GRP) and bombesin apparently enhance the rate of secretion of surfactant lipids from cultured fetal rat type II pneumocytes. This effect, evident within 1h of addition of the peptide, is concentration-dependent, with a maximal response at 3.0 nM. When the effect of GRP was assessed in comparison with other known secretagogues, it was found that, whereas GRP and isoproterenol were additive in their effect, there was no response to GRP in the presence of saturating concentrations of A23187 or phorbol 12-myristate 13-acetate. This suggests that the secretory response to GRP is via activation of Ca2+/calmodulin-dependent protein kinase and/or protein kinase C and is independent of adenosine 3',5'-cyclic monophosphate (cAMP)-dependent protein kinase. This conclusion is supported by the observation that the GRP-induced secretion is inhibited by calphostin C, an inhibitor of protein kinase C, but not by H-89, an inhibitor of cAMP-dependent protein kinase. The fact that GRP regulates surfactant secretion from type II pneumocytes suggests that it and/or related peptides may play a significant role in the physiological maturation of the lung.

Selected Contribution: PKC activation inhibits Ca2+ signaling in tracheal epithelial cells kept in simulated microgravity

2000 ◽  
Vol 89 (2) ◽  
pp. 855-864 ◽  
Author(s):  
Jennifer A. Felix ◽  
Ellen R. Dirksen ◽  
Michael L. Woodruff
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Simulated Microgravity ◽  
Tracheal Epithelial Cells ◽  
Kinase C ◽  
Tracheal Epithelial ◽  
Epithelial Sheets ◽  
Pkc Activation ◽  
Stimulation Of ◽  
In Cells

Microgravity has been shown to alter protein kinase C (PKC) activity; therefore, we investigated whether microgravity influences mechanically stimulated Ca2+signaling and ATP-induced Ca2+ oscillations, both of which are modulated by PKC. Rabbit tracheal epithelial outgrowth cultures or suspended epithelial sheets were rotated in bioreactors to simulate microgravity. Mechanical stimulation of a single cell increased the cytosolic Ca2+ concentration in 35–55 cells of both outgrowth cultures and epithelial sheets kept at unit gravity (G) or in simulated microgravity (sμG). In outgrowth cultures, 12- O-tetradecanoylphorbol-13-acetate (TPA; 80 nM), a PKC activator, restricted Ca2+ “waves” to about 10 cells in unit G and to significantly fewer cells in sμG. TPA only slightly reduced the spread of Ca2+ waves in epithelial sheets kept in sμG but did not inhibit Ca2+ waves of sheets kept in unit G. In both cell preparations from both conditions, TPA inhibited ATP-induced Ca2+ oscillations; however, the effect was more pronounced in cells kept in sμG. These results suggest that PKC activation is more robust in cells subjected to sμG.

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