Jessica S Helm

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Recent work from this laboratory has demonstrated that purinergic-mediated depolarization of human microglia inhibited a store-operated pathway for entry of Ca2+. We have used Fura-2 spectrofluorometry to investigate the effects on store-operated Ca2+ influx induced by replacement of NaCl with Na-gluconate in extracellular solutions. Three separate(More)
The input, processing, and output characteristics of inhibitory interneurons help shape information flow through layers 2/3 of the visual cortex. Parvalbumin (PV)-positive interneurons modulate and synchronize the gain and dynamic responsiveness of pyramidal neurons. To define the diversity of PV interneurons in layers 2/3 of the developing visual cortex,(More)
Activation of protein kinase C (PKC) potentiates secretion in Aplysia peptidergic neurons, in part by inducing new sites for peptide release at growth cone terminals. The mechanisms by which ion channels are trafficked to such sites are, however, not well understood. We now show that PKC activation rapidly recruits new Ca(V)2 subunits to the plasma(More)
The effects of extracellular acidification on Ca(2+)-dependent signaling pathways in human microglia were investigated using Ca(2+)-sensitive fluorescence microscopy. Adenosine triphosphate (ATP) was used to elicit Ca(2+) responses primarily dependent on the depletion of intracellular endoplasmic reticulum (ER) stores, while platelet-activating factor (PAF)(More)
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