Cell Reports,
Год журнала:
2024,
Номер
43(8), С. 114519 - 114519
Опубликована: Июль 16, 2024
Diverse
neuron
classes
in
hippocampal
CA1
have
been
identified
through
the
heterogeneity
of
their
cellular/molecular
composition.
How
these
relate
to
function
and
network
dynamics
that
support
cognition
primates
remains
unclear.
Here,
we
report
inhibitory
functional
cell
groups
freely
moving
macaques
whose
diverse
response
profiles
states
each
other
suggest
distinct
specific
roles
microcircuit
CA1.
In
addition,
pyramidal
cells
were
grouped
by
superficial
or
deep
layer
position
differed
firing
rate,
burstiness,
sharp-wave
ripple-associated
firing.
They
also
showed
strata-specific
spike-timing
interactions
with
groups,
suggestive
segregated
neural
populations.
Furthermore,
ensemble
recordings
revealed
assemblies
preferentially
organized
according
strata.
These
results
bears
a
sublayer-specific
circuit
organization
may
shape
its
role
cognition.
Neuron,
Год журнала:
2023,
Номер
111(20), С. 3154 - 3175
Опубликована: Июль 18, 2023
One
of
the
most
captivating
questions
in
neuroscience
revolves
around
brain's
ability
to
efficiently
and
durably
capture
store
information.
It
must
process
continuous
input
from
sensory
organs
while
also
encoding
memories
that
can
persist
throughout
a
lifetime.
What
are
cellular-,
subcellular-,
network-level
mechanisms
underlie
this
remarkable
capacity
for
long-term
information
storage?
Furthermore,
what
contributions
do
distinct
types
GABAergic
interneurons
make
process?
As
hippocampus
plays
pivotal
role
memory,
our
review
focuses
on
three
aspects:
(1)
delineation
hippocampal
interneuron
their
connectivity,
(2)
plasticity,
(3)
activity
patterns
during
memory-related
rhythms,
including
long-range
disinhibition.
We
explore
how
these
elements,
together
showcasing
diversity
inhibitory
circuits,
shape
processing
hippocampus.
Nature Communications,
Год журнала:
2023,
Номер
14(1)
Опубликована: Июль 19, 2023
Abstract
Episodic
memory-based
decision-making
requires
top-down
medial
prefrontal
cortex
and
hippocampal
interactions.
This
integrated
prefrontal-hippocampal
memory
state
is
thought
to
be
organized
by
synchronized
network
oscillations
mediated
connectivity
with
the
thalamic
nucleus
reuniens
(RE).
Whether
how
RE
synchronizes
networks
in
memory,
however,
remains
unknown.
Here,
we
recorded
local
field
potentials
from
prefrontal-RE-hippocampal
while
rats
engaged
a
nonspatial
sequence
task,
thereby
isolating
memory-related
activity
running-related
oscillations.
We
found
that
synchronous
beta
bursts
(15–30
Hz)
dominated
during
trials,
whereas
theta
(6–12
non-memory–related
running.
Moreover,
appeared
first,
followed
beta,
suggesting
could
driven
RE.
To
test
whether
capable
of
driving
synchrony,
used
an
optogenetic
approach
(retroAAV-ChR2).
activation
induced
coherence
reduced
coherence,
matching
observed
memory-driven
task.
These
findings
are
first
demonstrate
contributes
transient
system,
facilitating
interactions
underlie
decision-making.
Progress in Neurobiology,
Год журнала:
2024,
Номер
236, С. 102601 - 102601
Опубликована: Апрель 1, 2024
Here,
we
provide
an
in-depth
consideration
of
our
current
understanding
engrams,
spanning
from
molecular
to
network
levels,
and
hippocampal
neurogenesis,
in
health
Alzheimer's
disease
(AD).
This
review
highlights
novel
findings
these
emerging
research
fields
future
directions
for
therapeutic
avenues
memory
failure
dementia.
Engrams,
AD,
neurogenesis
have
each
been
extensively
studied.
The
integration
topics,
however,
has
relatively
less
deliberated,
is
the
focus
this
review.
We
primarily
on
dentate
gyrus
(DG)
hippocampus,
which
a
key
area
episodic
formation.
Episodic
significantly
impaired
also
site
adult
neurogenesis.
Advancements
technology,
especially
opto-
chemogenetics,
made
sophisticated
manipulations
engram
cells
possible.
Furthermore,
innovative
methods
emerged
monitoring
neurons,
even
specific
neuronal
populations,
vivo
while
animals
engage
tasks,
such
as
calcium
imaging.
In
imaging
contributes
more
comprehensive
cells.
Critically,
studies
DG
using
technologies
shown
important
contribution
both
AD.
Together,
discussion
topics
provides
holistic
perspective
that
motivates
questions
research.
Cell Reports,
Год журнала:
2024,
Номер
43(4), С. 114115 - 114115
Опубликована: Апрель 1, 2024
In
the
CA1
hippocampus,
vasoactive
intestinal
polypeptide-expressing
interneurons
(VIP-INs)
play
a
prominent
role
in
disinhibitory
circuit
motifs.
However,
specific
behavioral
conditions
that
lead
to
disinhibition
remain
uncertain.
To
investigate
relevance
of
VIP-IN
activity,
we
employed
wireless
technologies
allowing
us
monitor
and
manipulate
their
function
freely
behaving
mice.
Our
findings
reveal
that,
during
spatial
exploration
new
environments,
VIP-INs
hippocampal
region
become
highly
active,
facilitating
rapid
encoding
novel
information.
Remarkably,
both
pyramidal
neurons
(PNs)
exhibit
increased
activity
when
encountering
changes
environment,
including
context-
object-related
alterations.
Concurrently,
somatostatin-
parvalbumin-expressing
inhibitory
populations
show
an
inverse
relationship
with
PN
revealing
occurs
on
timescale
seconds.
Thus,
VIP-IN-mediated
may
constitute
crucial
element
novelty
acquisition
recognition
memory.
Understanding
the
plasticity
of
neuronal
networks
is
an
emerging
field
(patho-)
physiological
research,
yet
underlying
cellular
mechanisms
remain
poorly
understood.
Gamma
oscillations
(30
to
80
hertz),
a
biomarker
cognitive
performance,
require
and
potentiate
glutamatergic
transmission
onto
parvalbumin-positive
interneurons
(PVIs),
suggesting
interface
for
cell-to-network
plasticity.
In
ex
vivo
local
potential
recordings,
we
demonstrate
long-term
potentiation
hippocampal
gamma
power.
obeys
established
rules
PVI
plasticity,
requiring
calcium-permeable
AMPA
receptors
(CP-AMPARs)
metabotropic
glutamate
(mGluRs).
A
microcircuit
computational
model
CA3
predicts
CP-AMPAR
PVIs
critically
outperforms
pyramidal
cell
in
increasing
power
completely
accounts
potentiation.
We
reaffirm
this
three
PVI-targeting
animal
models,
demonstrating
that
requires
PVI-specific
signaling
via
Gq/PKC
pathway
comprising
mGluR5
Gi-sensitive,
PKA-dependent
pathway.
activity-dependent,
metabotropically
mediated
on
may
serve
as
guiding
principle
understanding
network
health
disease.
Nature Communications,
Год журнала:
2024,
Номер
15(1)
Опубликована: Янв. 24, 2024
Abstract
The
hippocampus
is
the
brain’s
center
for
episodic
memories.
Its
subregions,
dentate
gyrus
and
CA1-3,
are
differentially
involved
in
memory
encoding
recall.
Hippocampal
principal
cells
represent
features
like
movement,
space,
context,
but
less
known
about
GABAergic
interneurons.
Here,
we
performed
two-photon
calcium
imaging
of
parvalbumin-
somatostatin-expressing
interneurons
CA1-3
male
mice
exploring
virtual
environments.
Parvalbumin-interneurons
increased
activity
with
running-speed
reduced
it
novel
Somatostatin-interneurons
behaved
similar
to
parvalbumin-expressing
cells,
their
counterparts
during
rest
Congruently,
chemogenetic
silencing
parvalbumin-interneurons
had
prominent
effects
familiar
contexts,
while
similarity
granule
cell
representations
between
Our
data
indicate
unique
roles
somatostatin-positive
that
distinct
from
those
may
support
routing
information.
