The Functioning of the Frog’s Single Ventricle
Published: Oct. 1, 2023
African
clawed
frog
(Xenopus
laevis)
has
double-inlet
and
single-outlet
single
ventricle
supporting
both
systemic
pulmonary
circulations,
with
normal
lifespan
of
25-30
years.
The
relationship
between
blood
flows
was
investigated
using
echocardiography.
Twelve
female
frogs,
age
18-24
months,
mean
weight
173±19
grams
were
studied.
Heart
rate,
percutaneous
oxygen
saturation,
echocardiography
derived
2D
flow
in
all
cardiovascular
structures
measured
two
temperature
setting,
17◦C
(normal
environment
for
frogs)
22
C.
In
eight
frogs
cerebral
Near-Infra-Red
Spectroscopy
(NIRS)
measured.
Mean
saturation
66±9%
22◦C
85±6%
(P<0.001),
while
there
no
statistical
difference
heart
rates,
respectively
48
13
42±7
beats/min.
Doppler
showed
a
total
(QP)
=173.0
ml/min
(QS)
=
99.3ml/min,
QP/QS
1.74:1.00.
only
correlation
size
the
body
found
veins,
coefficient
0.71
(P=0.02).
NIRS
measurements
reverse
(coefficient
-0.21)
saturation.
frog’s
peculiar
morphologic
functional
characteristics
allowing
quality
life
many
years
despite
presence
ventricle.
Baseline
under
general
anesthesia
significant
increased
flow.
Exposure
to
environmental
5◦C
higher
than
caused
peripheral
vasodilatation,
subsequent
decrease
reduced
oxygenation.
Language: Английский
Cardiovascular Response to Exercise in Vertebrates: Update
Published: Jan. 17, 2024
Physical
exercise
is
the
greatest
stress
on
cardiovascular
system,
not
only
in
humans
but
also
all
vertebrates.
Consequently,
response
cannot
be
thought
of
as
having
one
"anthropocentric"
interpretation.
The
modulation
cardiac
output
(Q)
to
five
major
groups
vertebrates
exhibits
considerable
variability.
Moreover,
heart
rate
(HR)
and
stroke
volume
(SV),
fundamental
factors
that
cause
rise
Q,
highly
variable.
difference
range
HR
difficult
determine
many
vertebrates,
both
at
rest
maximal
effort.
Additionally,
increase
SV
varies
among
For
example,
while
rainbow
trout
leopards
their
by
increasing
end
diastolic
(EDV),
do
so
expense
EDV
reducing
systolic
(ESV).
variation
arterial
pressure
arises
during
notably
such
amphibians,
whose
blood
values
significantly
mammals.
Such
differences
may
linked
habitat
or
living
environment.
This
review
aims
analyze
physical
most
common
stressor.
Language: Английский
None
Published: Oct. 1, 2023
African
clawed
frog
(Xenopus
laevis)
has
double-inlet
and
single-outlet
single
ventricle
supporting
both
systemic
pulmonary
circulations,
with
normal
lifespan
of
25-30
years.The
relationship
between
blood
flows
was
investigated
using
echocardiography.Twelve
female
frogs,
age
18-24
months,
mean
weight
173±19
grams
were
studied.Heart
rate,
percutaneous
oxygen
saturation,
echocardiography
derived
2D
flow
in
all
cardiovascular
structures
measured
two
temperature
setting,
17
•
C
(normal
environment
for
frogs)
22
C.In
eight
frogs
cerebral
Near-Infra-Red
Spectroscopy
(NIRS)
measured.Mean
saturation
66±9%
85±6%
(P<0.001),
while
there
no
statistical
difference
heart
rates,
respectively
48
13
42±7
beats/min.Doppler
showed
a
total
(QP)
=173.0
ml/min
(QS)
=
99.3
ml/min,
QP/QS
1.74:1.00.The
only
correlation
size
the
body
found
veins,
coefficient
0.71
(P=0.02).NIRS
measurements
reverse
(coefficient
-0.21)with
saturation.The
frog's
peculiar
morphologic
functional
characteristics
allowing
quality
life
many
years
despite
presence
ventricle.Baseline
under
general
anesthesia
significant
increased
flow.Exposure
to
environmental
5
higher
than
caused
peripheral
vasodilatation,
subsequent
decrease
reduced
oxygenation.
Language: Английский