Journal of Neuroscience,
Journal Year:
2018,
Volume and Issue:
38(1), P. 3 - 13
Published: Jan. 3, 2018
A
major
controversy
persists
within
the
field
of
glial
biology
concerning
whether
or
not,
under
physiological
conditions,
neuronal
activity
leads
to
Ca2+-dependent
release
neurotransmitters
from
astrocytes,
a
phenomenon
known
as
gliotransmission.
Our
perspective
is
that,
while
we
and
others
can
apply
techniques
cause
gliotransmission,
there
considerable
evidence
gathered
using
astrocyte-specific
more
approaches
which
suggests
that
gliotransmission
pharmacological
rather
than
process.
Approaches
providing
against
include
stimulation
Gq-GPCRs
expressed
only
in
well
removal
primary
proposed
source
astrocyte
Ca2+
responsible
for
These
contrast
with
those
supportive
mechanical
stimulation,
strong
astrocytic
depolarization
whole-cell
patch-clamp
optogenetics,
uncaging
IP3,
chelating
BAPTA,
nonspecific
bath
application
agonists
receptors
by
multitude
cell
types.
are
not
subtle
therefore
recent
suggestions
requires
very
specific
delicate
temporal
spatial
requirements.
Other
evidence,
including
lack
propagating
waves
between
astrocytes
healthy
tissue,
expression
vesicular
machinery,
demise
d-serine
hypothesis,
provides
additional
Overall,
data
suggest
province
neurons,
intact
brain
conditions.Dual
Perspectives
Companion
Paper:
Gliotransmission:
Beyond
Black-and-White,
Iaroslav
Savtchouk
Andrea
Volterra.
Neuropsychopharmacology,
Journal Year:
2017,
Volume and Issue:
43(1), P. 4 - 20
Published: Sept. 1, 2017
Endocannabinoids
(eCBs)
are
amongst
the
most
ubiquitous
signaling
molecules
in
nervous
system.
Over
past
few
decades,
observations
based
on
a
large
volume
of
work,
first
examining
pharmacological
effects
exogenous
cannabinoids,
and
then
physiological
functions
eCBs,
have
directly
challenged
long-held
dogmatic
views
about
communication,
plasticity
behavior
central
system
(CNS).
The
eCBs
their
cognate
cannabinoid
receptors
exhibit
number
unique
properties
that
distinguish
them
from
widely
studied
classical
amino-acid
transmitters,
neuropeptides,
catecholamines.
Although
we
now
loose
set
mechanistic
rules
experimental
findings,
new
studies
continue
to
reveal
our
understanding
eCB
(ECS)
is
continuously
evolving
challenging
conventions.
Here
will
briefly
summarize
findings
current
canonical
view
‘ECS’
address
novel
aspects
how
nearly
can
determine
highly
specific
brain.
In
particular,
focus
push
for
an
expansion
ideas
around
beliefs
that,
while
clearly
true,
may
be
contributing
oversimplified
perspective
at
microscopic
level
impacts
macroscopic
level.
Glia,
Journal Year:
2019,
Volume and Issue:
67(12), P. 2221 - 2247
Published: Aug. 19, 2019
Abstract
Astrocytes
are
key
cellular
partners
for
neurons
in
the
central
nervous
system.
react
to
virtually
all
types
of
pathological
alterations
brain
homeostasis
by
significant
morphological
and
molecular
changes.
This
response
was
classically
viewed
as
stereotypical
is
called
astrogliosis
or
astrocyte
reactivity.
It
long
considered
a
nonspecific,
secondary
reaction
conditions,
offering
no
clues
on
disease‐causing
mechanisms
with
little
therapeutic
value.
However,
many
studies
over
last
30
years
have
underlined
crucial
active
roles
played
astrocytes
physiology,
ranging
from
metabolic
support,
synapse
maturation,
pruning
fine
regulation
synaptic
transmission.
prompted
researchers
explore
how
these
new
functions
were
changed
disease,
they
reported
them
(sometimes
beneficial,
mostly
deleterious).
More
recently,
cell‐specific
transcriptomics
revealed
that
undergo
massive
changes
gene
expression
when
become
reactive.
observation
further
stressed
reactive
may
be
very
different
normal,
nonreactive
could
influence
disease
outcomes.
To
make
picture
even
more
complex,
both
normal
shown
molecularly
functionally
heterogeneous.
Very
known
about
specific
each
subtype
play
contexts.
In
this
review,
we
interrogated
field
identify
discuss
points
consensus
controversies
astrocytes,
starting
their
name.
We
then
present
emerging
knowledge
cells
future
challenges
field.
Accumulating
evidence
indicates
that
astrocytes
are
actively
involved
in
brain
function
by
regulating
synaptic
activity
and
plasticity.
Different
gliotransmitters,
such
as
glutamate,
ATP,
GABA
or
D-serine,
released
form
have
been
shown
to
induce
different
forms
of
regulation.
However,
whether
a
single
astrocyte
may
release
gliotransmitters
is
unknown.
Here
we
show
mouse
hippocampal
activated
endogenous
(neuron-released
endocannabinoids
GABA)
exogenous
(single
Ca2+
uncaging)
stimuli
modulate
putative
CA3-CA1
synapses.
The
astrocyte-mediated
modulation
was
biphasic
consisted
an
initial
glutamate-mediated
potentiation
followed
purinergic-mediated
depression
neurotransmitter
release.
temporal
dynamic
properties
this
regulation
depended
on
the
firing
frequency
duration
neuronal
stimulated
astrocytes.
Present
results
indicate
can
decode
and,
response,
distinct
differentially
regulate
neurotransmission
at
Philosophical Transactions of the Royal Society B Biological Sciences,
Journal Year:
2017,
Volume and Issue:
372(1715), P. 20160154 - 20160154
Published: Jan. 17, 2017
Astrocytes
intimately
interact
with
synapses,
both
morphologically
and,
as
evidenced
in
the
past
20
years,
at
functional
level.
Ultrathin
astrocytic
processes
contact
and
sometimes
enwrap
synaptic
elements,
sense
transmission
shape
or
alter
signal
by
releasing
signalling
molecules.
Yet,
consequences
of
such
interactions
terms
information
processing
brain
remain
very
elusive.
This
is
largely
due
to
two
major
constraints:
(i)
exquisitely
complex,
dynamic
ultrathin
nature
distal
that
renders
their
investigation
highly
challenging
(ii)
our
lack
understanding
how
encoded
local
global
fluctuations
intracellular
calcium
concentrations
astrocytes.
Here,
we
will
review
existing
anatomical
evidence
between
astrocytes
it
underlies
a
role
for
computation
information.This
article
part
themed
issue
'Integrating
Hebbian
homeostatic
plasticity'.
