Expression of inflammatory secretory phospholipase A2 and cytosolic phospholipase A2 in premalignant and malignant Barrett?s oesophagus

2004 ◽  
Vol 444 (5) ◽  
pp. 426-435 ◽  
Author(s):  
Fran�ois Paraf ◽  
Christine Lagorce-Pag�s ◽  
Dominique Wendum ◽  
Antoine Martin ◽  
Jean-Fran�ois Fl�jou
Keyword(s):  
Phospholipase A2 ◽  
Cytosolic Phospholipase A2 ◽  
Secretory Phospholipase A2 ◽  
Secretory Phospholipase ◽  
Cytosolic Phospholipase

scholarly journals Studies on a Mechanism by Which Cytosolic Phospholipase A2 Regulates the Expression and Function of Type IIA Secretory Phospholipase A2

2000 ◽  
Vol 165 (7) ◽  
pp. 4024-4031 ◽  
Author(s):  
Hiroshi Kuwata ◽  
Shinji Yamamoto ◽  
Yoshitaka Miyazaki ◽  
Satoko Shimbara ◽  
Yoshihito Nakatani ◽  
...  
Keyword(s):  
Phospholipase A2 ◽  
Cytosolic Phospholipase A2 ◽  
Secretory Phospholipase A2 ◽  
Secretory Phospholipase ◽  
Cytosolic Phospholipase ◽  
And Function

Apical endocytosis of ricin in MDCK cells is regulated by the cyclooxygenase pathway

2000 ◽  
Vol 113 (7) ◽  
pp. 1213-1221
Author(s):  
A. Llorente ◽  
B. van Deurs ◽  
O. Garred ◽  
P. Eker ◽  
K. Sandvig
Keyword(s):  
Arachidonic Acid ◽  
Phospholipase A2 ◽  
Mdck Cells ◽  
Secretory Phospholipase A2 ◽  
Electron Microscopic ◽  
Membrane Ruffling ◽  
Secretory Phospholipase ◽  
Cytosolic Phospholipase ◽  
Microscopic Studies ◽  
Stimulation Of

Addition of arachidonic acid or stimulation of arachidonic acid production by secretory phospholipase A2 selectively upregulated apical endocytosis of ricin in MDCK cells without affecting basolateral endocytosis. Electron microscopic studies revealed that MDCK cells treated with secretory phospholipase A2 and incubated with horseradish peroxidase had an increased number of normal appearing peroxidase-labeled endosomes and no sign of membrane ruffling. Moreover, inhibition of basal arachidonic acid release, either by decreasing the cytosolic phospholipase A(2) activity or the diacylglycerol lipase activity, reduced the rate of apical endocytosis. Furthermore, indomethacin, an inhibitor of the cyclooxygenase pathway, counteracted the stimulation of endocytosis seen with both secretory phospholipase A2 and arachidonic acid, suggesting that formation of eicosanoids such as prostaglandins could be essential for the regulation. This idea was supported by the finding that prostaglandin E2, the predominant prostaglandin formed in kidney, also upregulated ricin uptake. The regulatory effect of the cyclooxygenase pathway on apical endocytosis of ricin was found to be independent of protein kinases A and C, which are known to selectively control apical clathrin-independent endocytosis in polarized cells.

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