RT info:eu-repo/semantics/article
T1 Local Calcium Transients Triggered by Single L-Type Calcium Channel Currents in Cardiac Cells
A1 López López, José Ramón
A1 Shacklock, Philip S.
A1 Balke, C. William
A1 Gil, Withrowl
K1 Células cardíacas
K1 Receptores de calcio
AB Excitation-contraction coupling was studied in mammalian cardiac cells in which the opening probability of L-type calcium (Ca2 +) channels was reduced. Confocal microscopy during voltage-clamp depolarization revealed distinct local transients inthe concentration of intracellular calcium ions ([Ca2 +]¡). When voltage was varied, the latency to occurrence and the relative probability of occurrence of local [Ca2 +]; transients varied as predicted if ca2 + release from the sarcoplasmic reticulum (SR) was linked tightly to Ca2 + flux through L-type Ca2 + channels but not to that through the Na-Ca exchanger or to average [Ca2 +];. Voltage had no effect on the amplitude of local [Ca2 +]; transients. Thus, the most efficacious "Ca2 + signal" for activating Ca2 + release from the SR may be a transient microdomain of high [Ca2 +]; beneath an individual, open L-type Ca2 + channel
PB American Association for the Advancement of Science
SN 0036-8075
YR 1995
FD 1995
LK http://uvadoc.uva.es/handle/10324/25016
UL http://uvadoc.uva.es/handle/10324/25016
LA eng
NO Science, vol.268, n.5213  p.1042-1045
NO Producción Científica
DS UVaDOC
RD 27-dic-2024