Inhibition of Na+/Ca2+ exchange by hexapeptide FRCRSFa in rat ventricular myocytes.
Abstract
AIM: To study the effect of Phe-Arg-Cys-Arg-Ser-Phe-CONH2 (FRCRSFa) on Na+/Ca2+
exchange and its specificity in rat ventricular myocytes.
METHODS: Na+/Ca2+ exchange current (INa+/Ca2+) and other currents were measured
using whole-cell voltage clamp technique.
RESULTS: A concentration-dependent inhibition of hexapeptide FRCRSFa on Na +/Ca2+
exchange was observed in rat ventricular myocytes. IC50 of inward and outward
INa+/Ca2+ were 2 and 4 micromol/L, respectively. FRCRSFa 5 micromol/L did not
affect L-type Ca2+ current, voltage-gated Na+ current, transient outward K+
current, and inward rectifier K+ current.
CONCLUSION: These data indicate that FRCRSFa is an available inhibitor of
Na+/Ca2+ exchange with relative selectivity and m ay be valuable for studies of
the Na+/Ca2+ exchange in cardiac myocytes.
Keywords:
exchange and its specificity in rat ventricular myocytes.
METHODS: Na+/Ca2+ exchange current (INa+/Ca2+) and other currents were measured
using whole-cell voltage clamp technique.
RESULTS: A concentration-dependent inhibition of hexapeptide FRCRSFa on Na +/Ca2+
exchange was observed in rat ventricular myocytes. IC50 of inward and outward
INa+/Ca2+ were 2 and 4 micromol/L, respectively. FRCRSFa 5 micromol/L did not
affect L-type Ca2+ current, voltage-gated Na+ current, transient outward K+
current, and inward rectifier K+ current.
CONCLUSION: These data indicate that FRCRSFa is an available inhibitor of
Na+/Ca2+ exchange with relative selectivity and m ay be valuable for studies of
the Na+/Ca2+ exchange in cardiac myocytes.