scholarly journals Acute Activation of the Renal Betaine/GABA Transporter in Response to a Decrease in Extracellular Calcium

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Nehal R. Parikh ◽  
Cherissa L. Vaughn ◽  
Lagina L. Williams ◽  
Stephen A. Kempson
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Growth Medium ◽  
Mdck Cells ◽  
Gaba Transporter ◽  
Cell Monolayers ◽  
Kinase C ◽  
Dependent Inhibition ◽  
Intracellular Ca ◽  
Protein Kinase C Inhibitor

The betaine/GABA transporter (BGT1) is important for osmoprotection in kidney medullary cells. We previously reported an acute (30 min) increase in extracellular Ca2+ caused dose dependent inhibition of BGT-1 in renal MDCK cells. To determine if extracellular Ca2+ might be a local regulator of BGT-1, we have tested the response to low Ca2+ serum-free growth medium (LCM, 0.05 mM Ca2+). Chronic treatment (8–24 h) of MDCK cell monolayers completely blocked hypertonic adaptation of BGT1 and disrupted tight junctions. In contrast, acute treatment activated BGT1 transport within 30 min in MDCK cells previously adapted to hypertonic growth medium containing normal Ca2+ (1.6 mM). Activation was significant after 60–90 min and was independent of medium osmolarity. Peak transport was increased 50% in isotonic LCM and 100% in hypertonic (500 mOsm) LCM over controls. The activation was reversed by restoration of normal Ca2+. Perfusion of Fura-2-loaded MDCK cells with LCM decreased intracellular Ca2+ by 31% within 6-7 min. Inclusion of staurosporine (0.6 μM), a protein kinase C inhibitor, potentiated the action of LCM. We suggest that activation of BGT1 by LCM may be due in part to inhibition of protein kinase C.

Regulation of eicosanoid biosynthesis by phorbol ester in Madin Darby canine kidney cells

1990 ◽  
Vol 259 (4) ◽  
pp. F698-F703 ◽  
Author(s):  
D. W. Coyne ◽  
M. Mordhorst ◽  
A. R. Morrison
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Mdck Cells ◽  
Pge2 Production ◽  
Madin Darby Canine Kidney ◽  
Kinase C ◽  
Protein Kinase C Inhibitor ◽  
Peptide Agonist ◽  
Darby Canine Kidney ◽  
Canine Kidney

We assessed the effects of the peptide agonist, bradykinin (BK), and phorbol myristate acetate (PMA) on prostaglandin E2 (PGE2) production, cyclooxygenase (COX) activity and mass, and arachidonic acid (AA) release in Madin Darby canine kidney (MDCK) cells. PMA stimulated PGE2 production by increasing both AA release and the activity of COX. Using [35S]methionine labeling and immunoprecipitation, we demonstrated that the increased COX activity is due to new COX synthesis. Actinomycin D and cycloheximide blocked the PMA-stimulated COX activity but not AA release. Both PMA-stimulated AA release and COX activity were reduced by the protein kinase C inhibitor staurosporine (STP). Glucocorticoids failed to alter PMA- or BK-stimulated PGE2 production was reduced by STP, indicating BK acts in part through protein kinase C activation. BK increased PGE2 production in PMA-treated cells, suggesting a protein kinase C-independent mechanism of action as well. BK did not stimulate any change in COX activity. We conclude that in MDCK cells PMA, but not BK, can stimulate both AA release and COX synthesis. Stimulation of COX synthesis requires either prolonged activation of protein kinase C and/or an additional nonprotein kinase C-mediated effect of PMA.

scholarly journals A protein kinase C inhibitor, staurosporine, activates phospholipase D via a pertussis toxin-sensitive GTP-binding protein in rabbit peritoneal neutrophils.

1992 ◽  
Vol 267 (33) ◽  
pp. 23554-23559 ◽  
Author(s):  
Y Kanaho ◽  
K Takahashi ◽  
U Tomita ◽  
T Iiri ◽  
T Katada ◽  
...  
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Phospholipase D ◽  
Pertussis Toxin ◽  
Binding Protein ◽  
Gtp Binding Protein ◽  
Kinase C ◽  
Gtp Binding ◽  
Protein Kinase C Inhibitor

Involvement of protein kinase C, tyrosine kinases, and Rho kinase in Ca2+ handling of human small arteries

2000 ◽  
Vol 279 (3) ◽  
pp. H1228-H1238 ◽  
Author(s):  
M. Carmen Martínez ◽  
Voahanginirina Randriamboavonjy ◽  
Patrick Ohlmann ◽  
Narcisse Komas ◽  
Juan Duarte ◽  
...  
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Signaling Pathways ◽  
Tyrosine Kinases ◽  
Rho Kinase ◽  
Free Medium ◽  
Kinase C ◽  
Intracellular Ca ◽  
Pkc Inhibitors ◽  
Continuous Presence

The mechanisms of Ca2+ handling and sensitization were investigated in human small omental arteries exposed to norepinephrine (NE) and to the thromboxane A2 analog U-46619. Contractions elicited by NE and U-46619 were associated with an increase in intracellular Ca2+ concentration ([Ca2+]i), an increase in Ca2+-independent signaling pathways, or an enhancement of the sensitivity of the myofilaments to Ca2+. The two latter pathways were abolished by protein kinase C (PKC), tyrosine kinase (TK), and Rho-associated protein kinase (ROK) inhibitors. In Ca2+-free medium, both NE and U-46619 elicited an increase in tension that was greatly reduced by PKC inhibitors and abolished by caffeine or ryanodine. After depletion of Ca2+ stores with NE and U-46619 in Ca2+-free medium, addition of CaCl2 in the continuous presence of the agonists produced increases in [Ca2+]i and contractions that were inhibited by nitrendipine and TK inhibitors but not affected by PKC inhibitors. NE and U-46619 induced tyrosine phosphorylation of a 42- or a 58-kDa protein, respectively. These results indicate that the mechanisms leading to contraction elicited by NE and U-46619 in human small omental arteries are composed of Ca2+ release from ryanodine-sensitive stores, Ca2+ influx through nitrendipine-sensitive channels, and Ca2+ sensitization and/or Ca2+-independent pathways. They also show that the TK pathway is involved in the tonic contraction associated with Ca2+ entry, whereas TK, PKC, and ROK mechanisms regulate Ca2+-independent signaling pathways or Ca2+sensitization.

scholarly journals Protein Kinase C Inhibitor Generates Stable Human Tolerogenic Dendritic Cells

2013 ◽  
Vol 191 (5) ◽  
pp. 2247-2257 ◽  
Author(s):  
Takuya Matsumoto ◽  
Hitoshi Hasegawa ◽  
Sachiko Onishi ◽  
Jun Ishizaki ◽  
Koichiro Suemori ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Protein Kinase C ◽  
Protein Kinase ◽  
Kinase C ◽  
Tolerogenic Dendritic Cells ◽  
Protein Kinase C Inhibitor

The protein kinase C inhibitor H-7 activates human neutrophils: effect on shape, actin polymerization, fluid pinocytosis and locomotion

1990 ◽  
Vol 96 (1) ◽  
pp. 99-106
Author(s):  
H.U. Keller ◽  
V. Niggli ◽  
A. Zimmermann ◽  
R. Portmann
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Actin Polymerization ◽  
Kinase Inhibitor ◽  
Human Neutrophils ◽  
Kinase C ◽  
Chemotactic Peptides ◽  
Protein Kinase C Inhibitor ◽  
Shape Changes ◽  
Stimulation Of

The present study demonstrates new properties of H-7. The protein kinase inhibitor H-7 is a potent activator of several neutrophil functions. Stimulation of initially spherical nonmotile neutrophils elicits vigorous shape changes within a few seconds, increases in cytoskeletal actin, altered F-actin distribution, increased adhesiveness and a relatively small increase in pinocytic activity. H-7 has also chemokinetic activities. Depending on the experimental condition, H-7 may elicit or inhibit neutrophil locomotion. It failed to induce chemotaxis. Thus, the response pattern elicited by H-7 is different from that of other leukocyte activators such as chemotactic peptides, PMA or diacylglycerols. The finding that H-7 can elicit shape changes, actin polymerization and pinocytosis suggests that these events can occur without activation of protein kinase C (PKC). PMA-induced shape changes and stimulation of pinocytosis were not inhibited by H-7.

Activators of protein kinase A and of protein kinase C inhibit MDCK cell myo-inositol and betaine uptake.

1995 ◽  
Vol 6 (6) ◽  
pp. 1559-1564
Author(s):  
A S Preston ◽  
A Yamauchi ◽  
H M Kwon ◽  
J S Handler
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Protein Kinase A ◽  
Translational Regulation ◽  
Mdck Cells ◽  
Relative Effect ◽  
Amino Acid Sequences ◽  
Prolonged Incubation ◽  
Kinase C ◽  
Kinase A

Amino acid sequences of the myo-inositol and betaine cotransporters that are induced in MDCK cells by hypertonicity include consensus sequences for phosphorylation by protein kinase A and by protein kinase C. To test for the effect of activation of protein kinases A and C on the activity of those cotransporters, MDCK cells were exposed to activators of each kinase and the activity of both cotransporters was assayed. Incubation with 8-bromoadenosine 3':5'-cyclic monophosphate (8Br-cAMP) or 3-isobutyl-1-methylxanthine (IBMX), activators of protein kinase A, and incubation with an active phorbol ester or with an active diacylglycerol, activators of protein kinase C, inhibited the activity of both cotransporters by about 30%. The relative effect of the activation of protein kinase A and of protein kinase C was similar in hypertonic and isotonic cells. The effects of activators of protein kinase A and of protein kinase C were not additive. The two cotransporters behaved differently when protein kinase C activity was down-regulated by prolonged incubation with a higher concentration of phorbol 12-myristate 13-acetate. There was a doubling of activity of the myo-inositol cotransporter and no change in the activity of the betaine cotransporter in hypertonic and isotonic cells. Although the mechanisms of the effects of activation of the two kinases remain to be established, it is clear that the kinases can mediate post-translational regulation of the uptake of compatible osmolytes.

Inhibition of Experimental Proliferative Vitreoretinopathy with Protein Kinase C Inhibitor (Chelerythrine Chloride) and Melatonin

2005 ◽  
Vol 220 (1) ◽  
pp. 17-22 ◽  
Author(s):  
Hamdi Er ◽  
Yusuf Turkoz ◽  
Bülent Mızrak ◽  
Hakan Parlakpınar
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Proliferative Vitreoretinopathy ◽  
Kinase C ◽  
Chelerythrine Chloride ◽  
Protein Kinase C Inhibitor
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