Fig. 8From: Astrocytes respond to a neurotoxic Aβ fragment with state-dependent Ca2+ alteration and multiphasic transmitter releaseAβ25–35 triggered astrocytic lysosome exocytosis. a Astrocytes co-labeled with the green fluorescent Ca2+ indicator OGB-1 AM and the red-fluorescent lysosomal marker FM4-64 (a1). Application of Aβ25–35 (6 µM) evoked Ca2+ elevation followed by asynchronous exocytosis of lysosomes, as reflected by FM dye destaining (a2, a3). b Aβ-evoked lysosomal exocytosis imaged with CD63-pHluorin. c Temporal distribution of lysosomal exocytosis obtained with FM dye and CD63-pHluorin (n = 51–62 lysosomes from five cells per condition). Inset, cumulative histogram showing the temporal coincidence for the two lysosomal markers (p = 0.7). d Permeabilization of lysosomes by GPN affected the Aβ25–35-induced glutamate release (iGluSnFR, dF/F0*s; n = 12 cells per condition; recording protocol is as Fig. 7e). e The presence of anion channel blocker DCPIB did not affect astrocyte lysosome release rate as measured by FM4-64 destaining (n = 10 cells per condition). Scale bars, 10 µm for a, 5 µm for bBack to article page