Effect of UV-B irradiation on release of arachidonic acid from B-16 melanoma cells.
B-16 melanoma cells in culture were prelabeled with (3H)-arachidonate, and exposed to UV radiation. Immediately after irradiation the cells released labeled materials. This UV-stimulated release was inhibited by mepacrine (20 microM) and calmodulin inhibitor W7 (0.5 microM). To determine the influence of extracellular Ca2+ on the UV-stimulated release, experiments were made with media containing various concentrations of Ca2+. The release decreased significantly at lower Ca2+ concentrations. These results suggest that Ca2+-calmodulin-dependent phospholipase A2 was involved in UV-stimulated release of radiolabeled materials, possibly arachidonic acid and its metabolites, from the cells.
Suematsu
T
T
Department of Medical Biochemistry, Kurume University School of Medicine, Japan.
Hidaka
T
T
Sakanashi
T
T
Sugiyama
M
M
Ogura
R
R
D001095:Arachidonic Acids / Q000096:biosynthesis*; D002118:Calcium / Q000032:analysis; D002147:Calmodulin / Q000037:antagonists & inhibitors; D008546:Melanoma, Experimental / Q000378:metabolism*; D011796:Quinacrine / Q000494:pharmacology; D014407:Tumor Cells, Cultured / Q000378:metabolism / Q000528:radiation effects; D014466:Ultraviolet Rays
D001095:Arachidonic Acids; D002147:Calmodulin; D011796:Quinacrine; D002118:Calcium