store-regulated Ca2+ influx in human neutrophils
نویسندگان
چکیده
1. It is not known to what extent the emptying of intracellular Ca2+ stores participates in the mediation of chemoattractantinduced Ca2+ influx in humawneutrophils. To study this question, we compared the properties of bivalent-cation influx in response to the chemoattractant N-formyl-L-methionyl-L-leucyl-L-phenylalanine (f-MLP) and to the microsomal Ca2+-ATPase inhibitor thapsigargin. 2. The influx pathway activated by f-MLP and thapsigargin had identical properties of permeation. Mn2+ influx became saturated at around 1 mM extracellular Mn2+, whereas Ca2+ influx did not become saturated up to concentrations of 10 mM. 3. The influx of the two bivalent cations, Mn2+ and Ca2 , was activated to a similar extent and with identical kinetics of
منابع مشابه
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