KB-R7943 inhibits the mitochondrial Ca2+ uniporter but not Na+-Ca2+ exchanger in cardiomyocyte-derived H9c2 cells

Iyuki Namekata, Ryosuke Odaka, Shogo Hamaguchi, Hikaru Tanaka
2020 Biological and Pharmaceutical Bulletin  
The effect of KB-R7943, an inhibitor of the plasmalemmal Na+-Ca2+ exchanger, on mitochondrial Ca2+ transporters was examined with membrane-permeabilized cardiomyocyte-derived H9c2 cells expressing the fluorescent Ca2+ indicator, yellow cameleon 3.1, in the mitochondria. KB-R7943, as well as ruthenium red, inhibited the rise in mitochondrial Ca2+ on increasing the extramitochondrial Ca2+ concentration from 0 nM to 300 nM. CGP37157, but not KB-R7943, inhibited the decline in mitochondrial Ca2+on
more » ... tochondrial Ca2+on return to Ca2+ free extramitochondrial solution. These results indicated that KB-R7943 has inhibitory effects on the mitochondrial Ca2+ uniporter, but not on the mitochondrial Na+-Ca2+ exchanger.
doi:10.1248/bpb.b20-00747 pmid:33028749 fatcat:ek5znzc2lvglfet764zzi3wuxe