Cyclic Ca2+ changes in intracellular stores of gonadotropes during gonadotropin-releasing hormone-stimulated Ca2+ oscillations.
AUTOR(ES)
Tse, F W
RESUMO
Gonadotropin-releasing hormone induces oscillatory release of Ca2+ from inositol trisphosphate-sensitive stores of gonadotropes. Simultaneously with electrophysiological measures of cytoplasmic [Ca2+], corresponding changes in [Ca2+] within intracellular stores were monitored with a fluorescent dye, mag-indo-1. Each cycle of oscillation released only 10% of the detectable stored Ca2+. Some Ca2+ was recovered by the stores using a mechanism sensitive to inhibitors of intracellular Ca2+ ATPases, and much of the remainder was temporarily and rapidly pumped into other intracellular compartments or out of the cell. The dynamics of Ca2+ oscillations are thus more complex than a repeated emptying and refilling of a single compartment. The free concentrations measured show that intracellular Ca2+ store compartments contain strong Ca2+ buffers.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=44894Documentos Relacionados
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