Protein kinase C dependent and independent activation of phospholipase A2 under calcium ionophore (A23187) exposure in rabbit pulmonary arterial smooth muscle cells.
Exposure of rabbit pulmonary arterial smooth muscle cells to the calcium ionophore A23187, dose-dependently stimulates arachidonic acid (AA) release and phospholipase A2 (PLA2) activity. The protein kinase C (PKC) inhibitor, sphingosine does not prevents AA release and PLA2 activity caused by low doses of A23187. In contrast, sphingosine markedly prevents AA release and PLA2 activity caused by higher doses of A23187. PKC activity profile indicates that treatment of the cells with low doses of A23187 does not cause significant alteration of PKC translocation from cytosol to membrane whereas higher concentrations of the ionophore dose-dependently enhance PKC translocation from cytosol to membrane in the smooth muscle cells.
Chakraborti
S
S
Department of Biochemistry and Biophysics, University of Kalyani, India.
Michael
J R
JR
Patra
S K
SK
D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism; D000001:Calcimycin / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D004789:Enzyme Activation; D008565:Membrane Proteins / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D010741:Phospholipases A / Q000378:metabolism*; D054467:Phospholipases A2; D011493:Protein Kinase C / Q000378:metabolism*; D011651:Pulmonary Artery; D011817:Rabbits; D015398:Signal Transduction; D013110:Sphingosine / Q000494:pharmacology
D001095:Arachidonic Acids; D008565:Membrane Proteins; D016718:Arachidonic Acid; D000001:Calcimycin; D011493:Protein Kinase C; D010741:Phospholipases A; D054467:Phospholipases A2; D013110:Sphingosine; D002118:Calcium