scholarly journals Requirement of phospholipase C and protein kinase C in cholecystokinin-mediated facilitation of NMDA channel function and anxiety-like behavior

Hippocampus ◽  
2011 ◽  
Vol 22 (6) ◽  
pp. 1438-1450 ◽  
Author(s):  
Zhaoyang Xiao ◽  
Manoj K. Jaiswal ◽  
Pan-Yue Deng ◽  
Toshimitsu Matsui ◽  
Hee-Sup Shin ◽  
...  
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Phospholipase C ◽  
Channel Function ◽  
Kinase C ◽  
Nmda Channel

Regulation of oxytocin secretion by the ovine corpus luteum: effect of activators of protein kinase C

1990 ◽  
Vol 124 (2) ◽  
pp. 225-232 ◽  
Author(s):  
J. J. Hirst ◽  
G. E. Rice ◽  
G. Jenkin ◽  
G. D. Thorburn
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Cyclic Amp ◽  
Corpus Luteum ◽  
Phospholipase C ◽  
Tissue Slices ◽  
Kinase C ◽  
Luteal Tissue ◽  
Dose Dependent ◽  
Stimulation Of

ABSTRACT The effect of protein kinase C activation and dibutyryl cyclic AMP on oxytocin secretion by ovine luteal tissue slices was investigated. Several putative regulators of luteal oxytocin secretion were also examined. Oxytocin was secreted by luteal tissue slices at a basal rate of 234·4 ± 32·8 pmol/g per h (n = 24) during 60-min incubations.Activators of protein kinase C: phorbol 12,13-dibutyrate (n = 8), phorbol 12-myristate,13-acetate (n = 4) and 1,2-didecanoylglycerol (n = 5), caused a dose-dependent stimulation of oxytocin secretion in the presence of a calcium ionophore (A23187; 0·2 μmol/l). Phospholipase C (PLC; 50–250 units/l) also caused a dose-dependent stimulation of oxytocin secretion by luteal slices. Phospholipase C-stimulated oxytocin secretion was potentiated by the addition of an inhibitor of diacylglycerol kinase (R59 022; n = 4). These data suggest that the activation of protein kinase C has a role in the stimulation of luteal oxytocin secretion. The results are also consistent with the involvement of protein kinase C in PLC-stimulated oxytocin secretion. The cyclic AMP second messenger system does not appear to be involved in the control of oxytocin secretion by the corpus luteum. Journal of Endocrinology (1990) 124, 225–232

scholarly journals Collagen-induced platelet activation mainly involves the protein kinase C pathway

1990 ◽  
Vol 268 (2) ◽  
pp. 325-331 ◽  
Author(s):  
A Karniguian ◽  
F Grelac ◽  
S Levy-Toledano ◽  
Y J Legrand ◽  
F Rendu
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Phospholipase C ◽  
Platelet Activation ◽  
Membrane Receptors ◽  
Lag Phase ◽  
Response Curves ◽  
Kinase C ◽  
Metabolic Event ◽  
Granule Secretion

This study analyses early biochemical events in collagen-induced platelet activation. An early metabolic event occurring during the lag phase was the activation of PtdIns(4,5)P2-specific phospholipase C. Phosphatidic acid (PtdOH) formation, phosphorylation of P43 and P20, thromboxane B2 (TXB2) synthesis and platelet secretion began after the lag phase, and were similarly time-dependent, except for TXB2 synthesis, which was delayed. Collagen induced extensive P43 phosphorylation, whereas P20 phosphorylation was weak and always lower than with thrombin. The dose-response curves of P43 phosphorylation and granule secretion were similar, and both reached a peak at 7.5 micrograms of collagen/ml, a dose which induced half-maximal PtdOH and TXB2 formation. Sphingosine, assumed to inhibit protein kinase C, inhibited P43 phosphorylation and secretion in parallel. However, sphingosine was not specific for protein kinase C, since a 15 microM concentration, which did not inhibit P43 phosphorylation, blocked TXB2 synthesis by 50%. Sphingosine did not affect PtdOH formation at all, even at 100 microM, suggesting that collagen itself induced this PtdOH formation, independently of TXB2 generation. The absence of external Ca2+ allowed the cleavage of polyphosphoinositides and the accumulation of InsP3 to occur, but impaired P43 phosphorylation, PtdOH and TXB2 formation, and secretion; these were only restored by adding 0.11 microM-Ca2+. In conclusion, stimulation of platelet membrane receptors for collagen initiates a PtdInsP2-specific phospholipase C activation, which is independent of external Ca2+, and might be the immediate receptor-linked response. A Ca2+ influx is indispensable to the triggering of subsequent platelet responses. This stimulation predominantly involves the protein kinase C pathway associated with secretion, and appears not to be mediated by TXB2, at least during its initial stage.

ANG II controls Na+-K+( NH 4 + )-2Cl−cotransport via 20-HETE and PKC in medullary thick ascending limb

1998 ◽  
Vol 274 (4) ◽  
pp. C1047-C1056 ◽  
Author(s):  
Hassane Amlal ◽  
Christian LeGoff ◽  
Catherine Vernimmen ◽  
Manoocher Soleimani ◽  
Michel Paillard ◽  
...  
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Phospholipase C ◽  
Thick Ascending Limb ◽  
Ang Ii ◽  
Diacylglycerol Lipase ◽  
Medullary Thick Ascending Limb ◽  
Kinase C ◽  
Cell Ph ◽  
Cytochrome P 450

Cell pH was monitored in medullary thick ascending limbs to determine effects of ANG II on Na+-K+([Formula: see text])-2Cl−cotransport. ANG II at 10−16to 10−12 M inhibited 30–50% ( P < 0.005), but higher ANG II concentrations were stimulatory compared with the 10−12 M ANG II level cotransport activity; eventually, 10−6 M ANG II stimulated 34% cotransport activity ( P < 0.003). Inhibition by 10−12M ANG II was abolished by phospholipase C (PLC), diacylglycerol lipase, or cytochrome P-450-dependent monooxygenase blockade; 10−12 M ANG II had no effect additive to inhibition by 20-hydroxyeicosatetranoic acid (20-HETE). Stimulation by 10−6 M ANG II was abolished by PLC and protein kinase C (PKC) blockade and was partially suppressed when the rise in cytosolic Ca2+ was prevented. All ANG II effects were abolished by DUP-753 (losartan) but not by PD-123319. Thus ≤10−12 M ANG II inhibits via 20-HETE, whereas ≥5 × 10−11 M ANG II stimulates via PKC Na+-K+([Formula: see text])-2Cl−cotransport; all ANG II effects involve AT1 receptors and PLC activation.

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