Human prostate cell lines from normal and tumourigenic epithelia differ in the pattern and control of choline lipid headgroups released into the medium on stimulation of protein kinase C

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

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Stimulation of protein kinase C and insulin release by 1-oleoyl-2-acetyl-glycerol

European Journal of Biochemistry ◽

10.1111/j.1432-1033.1985.tb08887.x ◽

1985 ◽

Vol 149 (1) ◽

pp. 23-27 ◽

Cited By ~ 31

Author(s):

Willy J. MALAISSE ◽

Marjorie E. DUNLOP ◽

Paulo C. F. MATHIAS ◽

Francine MALAISSE-LAGAE ◽

Abdullah SENER

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Insulin Release ◽

Kinase C ◽

Stimulation Of

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Nanog expression is negatively regulated by protein kinase C activities in human cancer cell lines

Carcinogenesis ◽

10.1093/carcin/bgt104 ◽

2013 ◽

Vol 34 (7) ◽

pp. 1497-1509 ◽

Cited By ~ 3

Author(s):

Wing-Keung Chu ◽

Pei-Min Dai ◽

Hsin-Lun Li ◽

Chia-Chu Pao ◽

Jan-Kan Chen

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Cell Lines ◽

Cancer Cell ◽

Human Cancer ◽

Cancer Cell Lines ◽

Human Cancer Cell ◽

Human Cancer Cell Lines ◽

Nanog Expression ◽

Kinase C

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Cytoplasmic [Ca2+] and intracellular pH in lymphocytes. Role of membrane potential and volume-activated Na+/H+ exchange.

The Journal of General Physiology ◽

10.1085/jgp.89.2.185 ◽

1987 ◽

Vol 89 (2) ◽

pp. 185-213 ◽

Cited By ~ 70

Author(s):

S Grinstein ◽

S Cohen

Keyword(s):

Protein Kinase C ◽

Membrane Potential ◽

Protein Kinase ◽

Intracellular Ph ◽

Enzyme Treatment ◽

Membrane Hyperpolarization ◽

Kinase C ◽

Free Media ◽

Stimulation Of

The effect of elevating cytoplasmic Ca2+ [( Ca2+]i) on the intracellular pH (pHi) of thymic lymphocytes was investigated. In Na+-containing media, treatment of the cells with ionomycin, a divalent cation ionophore, induced a moderate cytoplasmic alkalinization. In the presence of amiloride or in Na+-free media, an acidification was observed. This acidification is at least partly due to H+ (equivalent) uptake in response to membrane hyperpolarization since: it was enhanced by pretreatment with conductive protonophores, it could be mimicked by valinomycin, and it was decreased by depolarization with K+ or gramicidin. In addition, activation of metabolic H+ production also contributes to the acidification. The alkalinization is due to Na+/H+ exchange inasmuch as it is Na+ dependent, amiloride sensitive, and accompanied by H+ efflux and net Na+ gain. A shift in the pHi dependence underlies the activation of the antiport. The effect of [Ca2+]i on Na+/H+ exchange was not associated with redistribution of protein kinase C and was also observed in cells previously depleted of this enzyme. Treatment with ionomycin induced significant cell shrinking. Prevention of shrinking largely eliminated the activation of the antiport. Moreover, a comparable shrinking produced by hypertonic media also activated the antiport. It is concluded that stimulation of Na+/H+ exchange by elevation of [Ca2+]i is due, at least in part, to cell shrinking and does not require stimulation of protein kinase C.

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Differential responsiveness of intestinal epithelial cells to 1,25-dihydroxyvitamin D3--role of protein kinase C

Journal of Endocrinology ◽

10.1677/joe.0.1690145 ◽

2001 ◽

Vol 169 (1) ◽

pp. 145-151 ◽

Cited By ~ 19

Author(s):

HJ Armbrecht ◽

MA Boltz ◽

TL Hodam ◽

VB Kumar

Keyword(s):

Vitamin D ◽

Protein Kinase C ◽

Protein Kinase ◽

Cell Lines ◽

Phorbol Esters ◽

Mrna Levels ◽

Intestinal Epithelial ◽

Vitamin D Receptors ◽

Kinase C ◽

Crypt Cells

Non-transformed rat intestinal epithelial cell (IEC) lines were used to study the action of 1,25-dihydroxyvitamin D(3) (1,25(OH)2D) in the intestine. The capacity of 1,25(OH)2D to increase the expression of the cytochrome P450 component of the vitamin D 24-hydroxylase (CYP24) was determined in IEC-6 and IEC-18 cell lines. In IEC-6 cells, which are derived from crypt cells isolated from the whole small intestine, 1,25(OH)2D markedly increased expression of CYP24 protein and mRNA within 12 h. In contrast, in IEC-18 cells, which are derived from crypt cells from the ileum only, 1,25(OH)2D did not increase expression of CYP24 until 24-48 h. The maximal levels of CYP24 mRNA seen in the IEC-18 cells were only 31% of the maximal levels seen in the IEC-6 cells. In the presence of 1,25(OH)2D, phorbol esters rapidly increased CYP24 mRNA levels in IEC-18 cells from almost undetectable to levels seen in IEC-6 cells. Protein kinase inhibitors abolished the stimulation by 1,25(OH)2D and by phorbol esters in both cell lines. Stimulation of mRNA levels by phorbol esters required new protein synthesis but stimulation by 1,25(OH)2D did not. These studies demonstrated that the rapid action of 1,25(OH)2D in IEC-6 cells is related to the activation of protein kinase C, an event which is missing in the IEC-18 cells. This differential response to 1,25(OH)2D probably takes place at a post-receptor site, since the number of vitamin D receptors in each cell line was found to be similar.

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