Stephen L. Colegrove

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Rate equations for mitochondrial Ca2+ uptake and release and plasma membrane Ca2+ transport were determined from the measured fluxes in the preceding study and incorporated into a model of Ca2+ dynamics. It was asked if the measured fluxes are sufficient to account for the [Ca2+]i recovery kinetics after depolarization-evoked [Ca2+]i elevations. Ca2+(More)
We studied how mitochondrial Ca2+ transport influences [Ca2+](i) dynamics in sympathetic neurons. Cells were treated with thapsigargin to inhibit Ca2+ accumulation by SERCA pumps and depolarized to elevate [Ca2+(i); the recovery that followed repolarization was then examined. The total Ca2+ flux responsible for the [Ca2+](i) recovery was separated into(More)
The ER is a central element in Ca(2+) signaling, both as a modulator of cytoplasmic Ca(2+) concentration ([Ca(2+)](i)) and as a locus of Ca(2+)-regulated events. During surface membrane depolarization in excitable cells, the ER may either accumulate or release net Ca(2+), but the conditions of stimulation that determine which form of net Ca(2+) transport(More)
CICR from an intracellular store, here directly characterized as the ER, usually refers to net Ca(2)+ release that amplifies evoked elevations in cytosolic free calcium [Ca2+](i). However, the companion paper (Albrecht, M.A., S.L. Colegrove, J. Hongpaisan, N.B. Pivovarova, S.B. Andrews, and D.D. Friel. 2001. J. Gen. Physiol. 118:83-100) shows that in(More)
Many cells express ryanodine receptors (RyRs) whose activation is thought to amplify depolarizationevoked elevations in cytoplasmic Ca 2 concentration ([Ca 2 ] i ) through a process of Ca 2 -induced Ca 2 release (CICR). In neurons, it is usually assumed that CICR triggers net Ca 2 release from an ER Ca 2 store. However, since net ER Ca 2 transport depends(More)
Many cells express ryanodine receptors (RyRs) whose activation is thought to amplify depolarization-evoked elevations in cytoplasmic Ca2+ concentration [Ca2+](i) through a process of Ca2+ -induced Ca2+ release (CICR). In neurons, it is usually assumed that CICR triggers net Ca2+ release from an ER Ca2+ store. However, since net ER Ca 2+ transport depends on(More)
Rate equations for mitochondrial Ca 2 1 uptake and release and plasma membrane Ca 2 1 transport were determined from the measured fluxes in the preceding study and incorporated into a model of Ca 2 1 dynamics. It was asked if the measured fluxes are sufficient to account for the [Ca 2 1 ] i recovery kinetics after depolarization-evoked [Ca 2 1 ] i(More)
Many cells express ryanodine receptors (RyRs) whose activation is thought to amplify depolarizationevoked elevations in cytoplasmic Ca 2 concentration ([Ca 2 ] i ) through a process of Ca 2 -induced Ca 2 release (CICR). In neurons, it is usually assumed that CICR triggers net Ca 2 release from an ER Ca 2 store. However, since net ER Ca 2 transport depends(More)