Effect of nicotinic acid adenine dinucleotide phosphate on ryanodine calcium release channel in heart.
Nicotinic acid adenine dinucleotide phosphate (NAADP), a molecule derived from nicotinamide adenine dinucleotide phosphate (NADP+), is a recently identified nucleotide that activates Ca2+ release from intracellular stores in invertebrate eggs and in mammalian cells. NAADP could function as an intracellular messenger for mobilizing internal Ca2+ stores, however the targets and nature of NAADP-induced Ca2+ release are unknown. We report here that NAADP (3-10 microM) induces Ca2+ release from rat heart microsomes and that NAADP (1-10 microM) activates single ryanodine receptor/calcium release channels (RyR2) from dog heart incorporated into bilayer lipid membranes. The results indicate that NAADP may play a role in cardiac excitation-contraction coupling by acting on RyR2 channels.
Mojzisová
A
A
Institute of Molecular Physiology and Genetics, Slovak Academy of Sciences, Bratislava, Slovak Republic.
Krizanová
O
O
Záciková
L
L
Komínková
V
V
Ondrias
K
K
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002132:Calcium Radioisotopes; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D008861:Microsomes / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism*; D009249:NADP / Q000031:analogs & derivatives / Q000494:pharmacology*; D051381:Rats; D019837:Ryanodine Receptor Calcium Release Channel / Q000378:metabolism*
D002132:Calcium Radioisotopes; D019837:Ryanodine Receptor Calcium Release Channel; D009249:NADP; C024376:NAADP; D002118:Calcium