PMID- 27479868
OWN - NLM
STAT- MEDLINE
DCOM- 20180105
LR  - 20180306
IS  - 1098-1136 (Electronic)
IS  - 0894-1491 (Linking)
VI  - 64
IP  - 12
DP  - 2016 Dec
TI  - Ca(2+) transients in astrocyte fine processes occur via Ca(2+) influx in the 
      adult mouse hippocampus.
PG  - 2093-2103
LID - 10.1002/glia.23042 [doi]
AB  - Astrocytes display complex morphologies with an array of fine extensions 
      extending from the soma and the primary thick processes. Until the use of 
      genetically encoded calcium indicators (GECIs) selectively expressed in 
      astrocytes, Ca(2+) signaling was only examined in soma and thick primary 
      processes of astrocytes where Ca(2+) -sensitive fluorescent dyes could be imaged. 
      GECI imaging in astrocytes revealed a previously unsuspected pattern of 
      spontaneous Ca(2+) transients in fine processes that has not been observed 
      without chronic expression of GECIs, raising potential concerns about the effects 
      of GECI expression. Here, we perform two-photon imaging of Ca(2+) transients in 
      adult CA1 hippocampal astrocytes using a new single-cell patch-loading strategy 
      to image Ca(2+) -sensitive fluorescent dyes in the cytoplasm of fine processes. 
      We observed that astrocyte fine processes exhibited a high frequency of 
      spontaneous Ca(2+) transients whereas astrocyte soma rarely showed spontaneous 
      Ca(2+) oscillations similar to previous reports using GECIs. We exploited this 
      new approach to show these signals were independent of neuronal spiking, 
      metabotropic glutamate receptor (mGluR) activity, TRPA1 channels, and L- or 
      T-type voltage-gated calcium channels. Removal of extracellular Ca(2+) almost 
      completely and reversibly abolished the spontaneous signals while IP(3) R2 KO 
      mice also exhibited spontaneous and compartmentalized signals, suggesting they 
      rely on influx of extracellular Ca(2+) . The Ca(2+) influx dependency of the 
      spontaneous signals in patch-loaded astrocytes was also observed in astrocytes 
      expressing GCaMP3, further highlighting the presence of Ca(2+) influx pathways in 
      astrocytes. The mechanisms underlying these localized Ca(2+) signals are critical 
      for understanding how astrocytes regulate important functions in the adult brain. 
      GLIA 2016;64:2093-2103.
CI  - (c) 2016 Wiley Periodicals, Inc.
FAU - Rungta, Ravi L
AU  - Rungta RL
AD  - Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 
      Vancouver, BC, V6T 2B5, Canada.
FAU - Bernier, Louis-Philippe
AU  - Bernier LP
AD  - Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 
      Vancouver, BC, V6T 2B5, Canada.
FAU - Dissing-Olesen, Lasse
AU  - Dissing-Olesen L
AD  - Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 
      Vancouver, BC, V6T 2B5, Canada.
FAU - Groten, Christopher J
AU  - Groten CJ
AD  - Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 
      Vancouver, BC, V6T 2B5, Canada.
FAU - LeDue, Jeffrey M
AU  - LeDue JM
AD  - Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 
      Vancouver, BC, V6T 2B5, Canada.
FAU - Ko, Rebecca
AU  - Ko R
AD  - Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 
      Vancouver, BC, V6T 2B5, Canada.
FAU - Drissler, Sibyl
AU  - Drissler S
AD  - Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 
      Vancouver, BC, V6T 2B5, Canada.
FAU - MacVicar, Brian A
AU  - MacVicar BA
AD  - Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 
      Vancouver, BC, V6T 2B5, Canada. bmacvicar@brain.ubc.ca.
LA  - eng
GR  - #8545/CIHR/Canada
GR  - 115121/CIHR/Canada
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20160801
PL  - United States
TA  - Glia
JT  - Glia
JID - 8806785
RN  - 0 (7-(hydroxyimino)cyclopropan(b)chromen-1a-carbxoylic acid ethyl ester)
RN  - 0 (Cacna1d protein, mouse)
RN  - 0 (Calcium Channels, L-Type)
RN  - 0 (Chromones)
RN  - 0 (Excitatory Amino Acid Antagonists)
RN  - 0 (Excitatory Amino Acid Transporter 1)
RN  - 0 (Inositol 1,4,5-Trisphosphate Receptors)
RN  - 0 (Ip3r2 protein, mouse)
RN  - 0 (Luminescent Proteins)
RN  - 0 (Pyridines)
RN  - 0 (Slc1a3 protein, mouse)
RN  - 0 (TRPA1 Cation Channel)
RN  - 0 (Trpa1 protein, mouse)
RN  - 7VC0YVI27Y (6-methyl-2-(phenylethynyl)pyridine)
RN  - MM6384NG73 (Carbenoxolone)
RN  - SY7Q814VUP (Calcium)
SB  - IM
MH  - Action Potentials/drug effects
MH  - Animals
MH  - Astrocytes/*metabolism
MH  - Calcium/*metabolism
MH  - Calcium Channels, L-Type/genetics/metabolism
MH  - Calcium Signaling/drug effects
MH  - Carbenoxolone/pharmacology
MH  - Chromones/pharmacology
MH  - Excitatory Amino Acid Antagonists/pharmacology
MH  - Excitatory Amino Acid Transporter 1/genetics/metabolism
MH  - Female
MH  - Hippocampus/*cytology
MH  - In Vitro Techniques
MH  - Inositol 1,4,5-Trisphosphate Receptors/genetics/metabolism
MH  - Luminescent Proteins/genetics/metabolism
MH  - Male
MH  - Membrane Microdomains/drug effects/metabolism
MH  - Mice
MH  - Mice, Inbred C57BL
MH  - Mice, Transgenic
MH  - Pyridines/pharmacology
MH  - TRPA1 Cation Channel/genetics/metabolism
OTO - NOTNLM
OT  - Calcium Green-1 dextran
OT  - Fluo-4
OT  - GCaMP
OT  - IP3R2
OT  - TRPA1
OT  - calcium channel
OT  - glia
OT  - microdomain
OT  - synaptic
OT  - two-photon
EDAT- 2016/10/21 06:00
MHDA- 2018/01/06 06:00
CRDT- 2016/08/02 06:00
PHST- 2016/03/14 00:00 [received]
PHST- 2016/07/13 00:00 [accepted]
PHST- 2016/10/21 06:00 [pubmed]
PHST- 2018/01/06 06:00 [medline]
PHST- 2016/08/02 06:00 [entrez]
AID - 10.1002/glia.23042 [doi]
PST - ppublish
SO  - Glia. 2016 Dec;64(12):2093-2103. doi: 10.1002/glia.23042. Epub 2016 Aug 1.