SERCA, complex I of the respiratory chain and ATP-synthase inhibition are involved in pleiotropic effects of NS1619 on endothelial cells.
A large conductance potassium (BKCa) channel opener, NS1619 (1,3-dihydro-1- [2-hydroxy-5-(trifluoromethyl) phenyl]-5-(trifluoromethyl)-2H-benzimidazole-2-one), is well known for its protective effects against ischemia-reperfusion injury; however, the exact mode of its action remains unclear. The aim of this study was to characterize the effect of NS1619 on endothelial cells. The endothelial cell line EA.hy926, guinea pig hearts and submitochondrial particles isolated from the heart were used. In the isolated guinea pig hearts, which were perfused using the Langendorff technique, NS1619 caused a dose-dependent increase in coronary flow that was inhibited by L-NAME. In EA.hy926 cells, NS1619 also caused a dose-dependent increase in the intracellular calcium ion concentration [Ca(2+)]i, as measured using the FURA-2 fluorescent probe. Moreover, NS1619 decreased the oxygen consumption rate in EA.hy926 cells, as assessed using a Clark-type oxygen electrode. However, when NS1619 was applied in the presence of oligomycin, the oxygen consumption increased. NS1619 also decreased the mitochondrial membrane potential, as measured using a JC-1 fluorescent probe in the presence and absence of oligomycin. Additionally, the application of NS1619 to submitochondrial particles inhibited ATP synthase. In summary, NS1619 has pleiotropic actions on EA.hy926 cells and acts not only as an opener of the BKCa channel in EA.hy926 cells but also as an inhibitor of the respiratory chain component, sarcoplasmic reticulum ATPase, which leads to the release of Ca(2+) from the endoplasmic reticulum. Furthermore, NS1619 has the oligomycin-like property of inhibiting mitochondrial ATP synthase.
Department of Biophysics, Warsaw University of Life Sciences SGGW, 159 Nowoursynowska St., 02-776 Warsaw, Poland. Electronic address: agnieszka_lukasiak@sggw.pl.
Agnieszka
A
Łukasiak
Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, 3 Pasteura St., 02-093 Warsaw, Poland.
Agata
A
Skup
Jagiellonian Centre for Experimental Therapeutics (JCET), Jagiellonian University, 14 Bobrzynskiego St., 30-348 Krakow, Poland; Chair of Pharmacology, Jagiellonian University, Medical College, 16 Grzegorzecka, 31-531 Krakow, Poland.
Stefan
S
Chlopicki
Chair of Pharmacology, Jagiellonian University, Medical College, 16 Grzegorzecka, 31-531 Krakow, Poland.
Magdalena
M
Łomnicka
Jagiellonian Centre for Experimental Therapeutics (JCET), Jagiellonian University, 14 Bobrzynskiego St., 30-348 Krakow, Poland.
Patrycja
P
Kaczara
Jagiellonian Centre for Experimental Therapeutics (JCET), Jagiellonian University, 14 Bobrzynskiego St., 30-348 Krakow, Poland.
Bartosz
B
Proniewski
Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, 3 Pasteura St., 02-093 Warsaw, Poland.
Adam
A
Szewczyk
Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, 3 Pasteura St., 02-093 Warsaw, Poland.
Antoni
A
Wrzosek
D000818:Animals; D001562:Benzimidazoles / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism; D002417:Cattle; D002460:Cell Line; D004721:Endoplasmic Reticulum / Q000187:drug effects / Q000378:metabolism; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006168:Guinea Pigs; D006801:Humans; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008929:Mitochondria, Heart / Q000187:drug effects / Q000378:metabolism; D025261:Mitochondrial Proton-Translocating ATPases / Q000037:antagonists & inhibitors*; D009569:Nitric Oxide / Q000096:biosynthesis / Q000378:metabolism; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases / Q000037:antagonists & inhibitors*; D014665:Vasodilator Agents / Q000494:pharmacology*
D001562:Benzimidazoles; D004791:Enzyme Inhibitors; D014665:Vasodilator Agents; C086491:NS 1619; D009569:Nitric Oxide; D025261:Mitochondrial Proton-Translocating ATPases; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases; D002118:Calcium
Endothelial cells; Mitochondria; Potassium channel openers