Bramble, D. M. and D.
R. Carrier (1983). "Running and breathing in
mammals." Science 219(4582): 251-6.
Mechanical constraints appear to require
that locomotion and breathing be synchronized in
running mammals. Phase locking of limb and
respiratory frequency has now been recorded
during treadmill running in jackrabbits and
during locomotion on solid ground in dogs,
horses, and humans. Quadrupedal species normally
synchronize the locomotor and respiratory cycles
at a constant ratio of 1:1 (strides per breath)
in both the trot and gallop. Human runners
differ from quadrupeds in that while running
they employ several phase-locked patterns (4:1,
3:1, 2:1, 1:1, 5:2, and 3:2), although a 2:1
coupling ratio appears to be favored. Even
though the evolution of bipedal gait has reduced
the mechanical constraints on respiration in
man, thereby permitting greater flexibility in
breathing pattern, it has seemingly not
eliminated the need for the synchronization of
respiration and body motion during sustained
running. Flying birds have independently
achieved phase-locked locomotor and respiratory
cycles. This hints that strict
locomotor-respiratory coupling may be a vital
factor in the sustained aerobic exercise of
endothermic vertebrates, especially those in
which the stresses of locomotion tend to deform
the thoracic complex.
Fugl-Meyer, A.
R., H. Linderholm, et al. (1983). "Restrictive
ventilatory dysfunction in stroke: its relation
to locomotor function." Scand J Rehabil Med
Suppl 9: 118-24.
Static and dynamic lung volumes, maximum
respiratory pressures and lung compliance and
resistance were registered in 54 subjects with
hemiplegia or hemiparesis after stroke. These
measures of ventilatory function were related to
the degree of motor impairment and to the
interval between stroke and investigation. In
general ventilatory function, particularly
parameters depending upon expiratory force, was
restricted. This was most pronounced in subjects
with severe hemiplegia while those with
hemiparesis had only small changes. Since
dynamic lung volumes (corrected for volume
loss), lung compliance and resistance were all
normal, it is evident that intrinsic lung
function was unaffected. Inspiratory capacity -
but no other measured variables of respiratory
function - was lower six months after the stroke
than earlier. It is suggested that expiratory
muscle dys-coordination and weakness caused
expiratory dysfunction while the less pronounced
inspiratory restriction may be caused by
muscular dysfunction and, as time goes by rib
cage contracture.
Viala, D.
(1986). "Evidence for direct reciprocal
interactions between the central rhythm
generators for spinal "respiratory" and
locomotor activities in the rabbit." Exp Brain
Res 63(2): 225-32.
Rhythm generators for locomotion and
respiration have been previously identified in
the high spinal rabbit treated with nialamide
and DOPA. In curarized preparations, with no
sensory feedback, simultaneous recordings of
motor commands from the nerves to the diaphragm
and to several hindlimb nerves have demonstrated
that central (intraspinal) interactions exist
between these respiratory and locomotor
activities. The purpose of the present study was
to investigate the nature of these interactions.
Two main possibilities existed: "direct"
interactions taking place between the rhythm
generators; the activity of one of the rhythm
generators modifying the other generator's
activity at its "output" (at the interneuronal
or motoneuronal level). The present analysis of
the timing (and resetting) of activities in the
phrenic, hindlimb extensor (gastrocnemius
medialis) and flexor (tibialis anterior) nerves
suggests a strong direct interaction between the
two sets of rhythm generators. Each new
locomotor cycle thus only begins at the
termination of a "long-lasting phrenic burst"
and a respiratory burst can only occur at
certain parts of a locomotor cycle.
Persegol, L.,
M. Jordan, et al. (1988). "Evidence for central
entrainment of the medullary respiratory pattern
by the locomotor pattern in the rabbit." Exp
Brain Res 71(1): 153-62.
1) Although periodic passive hindlimb
movements can reproduce the enhancement of
breathing frequency seen at the onset of
muscular exercise, we have shown previously that
they were unable to induce the 1:1 coupling
which is observed between locomotion and
respiration during galloping in quadrupeds. The
purpose of this study was to investigate the
existence of a central coupling in two
experimental situations: first, decorticate -
DOPA, and secondly, decerebrate rabbit
preparations. 2) After DOPA administration in
curarized, vagotomized, decorticate animals, an
absolute coordination could be observed between
the locomotor bursts (which developed in
hindlimb muscle nerves) and phrenic activity.
With the temporal evolution of the
pharmacological activation, the coupling mode
varied from 1:1 to 1:2 during the same
experiment with a loss of coordination between
these two forms. When the coordination between
both motor activities was not produced in such
conditions, it could be induced for some imposed
frequencies of periodic passive motions applied
to the contralateral hindlimb. 3) When the DOPA
effects were completely over, a rostro-pontine
decerebration allowed locomotor activity to be
released and a tight 1:1 coupling could be
obtained again between the two motor patterns in
this new experimental situation. 4) An analysis
of the data revealed that the various forms of
coordination obtained in the different
experimental situations are due to a central
resetting of the respiratory and of the
locomotor patterns. The capability of the
hindlimb proprioceptive inputs to coordinate
locomotor and respiratory patterns in the
decorticate-DOPA preparation appeared simply
linked to their ability to entrain the activity
of the lumbar locomotion generator. It is
suggested that these central reciprocal
interactions, which have the properties of an
entrainment process, are the result of
interactions between the lumbar locomotion
generator and the medullary respiratory
one.
Persegol,
L., M. Jordan, et al. (1991). "Evidence for the
entrainment of breathing by locomotor pattern in
human." J Physiol (Paris) 85(1): 38-43.
In human, it has been shown that
interactions between locomotor and respiratory
patterns may lead to locomotor-respiratory
couplings termed entrainment. In order to prove
that this coupling is really an entrainment, we
tried to show that it obeys one of the expected
rules, i.e. that it evolves and is not present
for all imposed locomotor frequencies. For that
purpose, seventeen healthy volunteers were asked
to run on a treadmill at 14 different locomotor
rates (instead of 2 or 3 in previous works) for
40 s. All the subjects did not exhibit the same
coupling and different relationships could be
obtained: the most commonly observed was 2:1 (2
locomotor activities for a respiratory one) but
other forms could appear (4:1 and even 5:2 or
3:2). When the coupling evolution was followed
in the same subject, it did not appear for all
locomotor frequencies but only for locomotor
periods close to harmonics of respiratory ones
(absolute coordination). On both sides of these
values, it progressively evolved to relative
coordination and to the lack of coordination.
When two forms of absolute coordination were
observed in a same subject, the phase
relationships followed the rules of the
entrainment. Compared to data obtained in
quadrupeds, these results suggest that the
entrainment of breathing frequency by the
locomotor activity is due to central
interactions between the respiratory and
locomotor pattern generators and does not depend
on a chemical regulation avoided here by short
locomotor sequences.
Kawahara, K.,
Y. Yamauchi, et al. (1994). "Interactions
between respiratory, cardiac and stepping
rhythms in decerebrated cats: functional
hierarchical structures of biological
oscillators." Methods Inf Med 33(1):
129-32.
Interactions are described of central origin
between respiratory, cardiac and stepping
rhythms during fictive locomotion in paralyzed,
vagotomized, and decerebrated cats. Fictive
locomotion was induced by tonic electrical
stimulation of the mesencephalic locomotor
region (MLR). The coherence between heart beat
fluctuation, the efferent discharges of the
phrenic, and the lateral gastrocnemius nerves
was used to evaluate the strength of the
coupling between those three rhythms. The heart
beat rhythm was modulated by the centrally
generated respiratory and stepping rhythms. The
central respiratory rhythm was modulated by the
centrally generated stepping rhythm. Based on
the present findings, we have proposed a new
model concerning the functional hierarchical
structures of the three biological
oscillators.
Romaniuk,
J. R., S. Kasicki, et al. (1994). "Respiratory
responses to stimulation of spinal or medullary
locomotor structures in decerebrate cats." Acta
Neurobiol Exp (Warsz) 54(1): 11-7.
Respiratory and locomotor EMG activity was
recorded in cats after a precollicular
post-mamillary decerebration. Locomotion was
induced by stimulating either the dorsolateral
funiculus (DLF) in the cervical spinal cord or
the medullary locomotor strip (MLS). At the
onset of locomotion, both ventilation and blood
pressure were enhanced. During locomotion, the
activity of external intercostal muscles
decreased but that of the internal intercostal
muscles increased. The respiratory pattern
changed with the onset of stimulation. The
locomotor movements were evoked after a delay.
The inspiratory-inhibitory Hering-Breuer reflex
was attenuated. Stimulation of the MLS and DLF
evoked similar respiratory and circulatory
effects. Our data resemble the effects observed
during stimulation of the subthalamic or
mesencephalic locomotor regions. We conclude
that respiratory changes are part of an
integrated response involved in the onset of
exercise and are independent of the neuronal
site where stimulation evoked locomotion. In
contrast to previous reports, we suggest that
the pattern of interaction among respiratory,
circulatory, and locomotor systems does not have
to be the specialty of supramedullary
structures. Coupling between locomotion and
breathing during the post-inspiratory phase
suggests that this interaction occurs at the
medullary level.
Persegol,
L., M. Jordan, et al. (1988). "Evidence for
central entrainment of the medullary respiratory
pattern by the locomotor pattern in the rabbit."
Exp Brain Res 71(1): 153-62.
1) Although periodic passive hindlimb
movements can reproduce the enhancement of
breathing frequency seen at the onset of
muscular exercise, we have shown previously that
they were unable to induce the 1:1 coupling
which is observed between locomotion and
respiration during galloping in quadrupeds. The
purpose of this study was to investigate the
existence of a central coupling in two
experimental situations: first, decorticate -
DOPA, and secondly, decerebrate rabbit
preparations. 2) After DOPA administration in
curarized, vagotomized, decorticate animals, an
absolute coordination could be observed between
the locomotor bursts (which developed in
hindlimb muscle nerves) and phrenic activity.
With the temporal evolution of the
pharmacological activation, the coupling mode
varied from 1:1 to 1:2 during the same
experiment with a loss of coordination between
these two forms. When the coordination between
both motor activities was not produced in such
conditions, it could be induced for some imposed
frequencies of periodic passive motions applied
to the contralateral hindlimb. 3) When the DOPA
effects were completely over, a rostro-pontine
decerebration allowed locomotor activity to be
released and a tight 1:1 coupling could be
obtained again between the two motor patterns in
this new experimental situation. 4) An analysis
of the data revealed that the various forms of
coordination obtained in the different
experimental situations are due to a central
resetting of the respiratory and of the
locomotor patterns. The capability of the
hindlimb proprioceptive inputs to coordinate
locomotor and respiratory patterns in the
decorticate-DOPA preparation appeared simply
linked to their ability to entrain the activity
of the lumbar locomotion generator. It is
suggested that these central reciprocal
interactions, which have the properties of an
entrainment process, are the result of
interactions between the lumbar locomotion
generator and the medullary respiratory
one.
Richard, C.
A., T. G. Waldrop, et al. (1989). "The nucleus
reticularis gigantocellularis modulates the
cardiopulmonary responses to central and
peripheral drives related to exercise." Brain
Res 482(1): 49-56.
It is known that muscle afferents and the
hypothalamic locomotor region (HLR) both project
to the nucleus reticularis gigantocellularis
(NGC) and that the NGC is capable of influencing
cardiovascular and respiratory variables.
Therefore, the role of NGC in the cardiovascular
and respiratory response to exercise-related
signals was investigated in anesthetized cats.
These signals were generated by stimulation of:
(1) spinal ventral roots to induce hindlimb
muscle contraction (MC) and (2) the HLR.
Bilateral electrolytic lesion of the NGC at the
pontomedullary border caused tidal volume,
respiratory frequency and heart rate responses
to HLR stimulation to be greater than the
responses recorded prior to lesioning. Lesioning
had no effect on the ventilatory or
cardiovascular responses to MC but did decrease
phrenic responsiveness; lesion had no effect on
any resting values. In this preparation, the
pontomedullary NGC acts as an inhibitory
influence on tidal volume, breathing frequency
and heart rate responses to the central command
for exercise. In addition, NGC modulation of
ventilation would appear to be selective for
certain respiratory muscle groups.
Greer, J. J.,
J. C. Smith, et al. (1992). "Respiratory and
locomotor patterns generated in the fetal rat
brain stem-spinal cord in vitro." J Neurophysiol
67(4): 996-9.
An in vitro brain stem-spinal cord
preparation from last trimester (E13-E21) fetal
rats, which generates rhythmic respiratory and
locomotor patterns, is described. These
coordinated motor patterns emerge at stages
E17-E18. Synchronous rhythmic motor activity,
not clearly characterized as respiratory or
locomotor, can occur as early as E13. With this
preparation, it is now possible to study the
ontogenesis of circuits and cellular mechanisms
underlying these critical movements.
Funk, G. D., J.
D. Steeves, et al. (1992). "Coordination of
wingbeat and respiration in birds. II. "Fictive"
flight." J Appl Physiol 73(3): 1025-33.
To determine whether an interaction between
central respiratory and locomotor networks may
be involved in the observed coordination of
wingbeat and respiratory rhythms during free
flight in birds, we examined the relationship
between wingbeat and respiratory activity in
decerebrate Canada geese and Pekin ducks before
and after paralysis. Locomotor activity was
induced through electrical stimulation of brain
stem locomotor regions. Respiratory frequency
(fv) was monitored via pneumotachography and
intercostal electromyogram recordings before
paralysis and via intercostal and cranial nerve
IX electroneurogram recordings after paralysis.
Wingbeat frequency (fW) was monitored using
pectoralis major electromyogram recordings
before, and electroneurogram recordings after,
paralysis. Respiratory and cardiovascular
responses of decerebrate birds during active
(nonparalyzed) and "fictive" (paralyzed) wing
activity were qualitatively similar to those of
a variety of vertebrate species to exercise. As
seen during free flight, wingbeat and
respiratory rhythms were always coordinated
during electrically induced wing activity.
Before paralysis during active wing flapping,
coupling ratios (fW/fv) of 1:1, 2:1, 3:1, and
4:1 (wingbeats per breath) were observed. After
paralysis, fW and fv remained coupled; however,
1:1 coordination predominated. All animals
tested (n = 9) showed 1:1 coordination. Two
animals also showed brief periods of 2:1
coupling. It is clear that locomotor and
respiratory networks interact on a central level
to produce a synchronized output. The
observation that the coordination between fW and
fv differs in paralyzed and nonparalyzed birds
suggests that peripheral feedback is involved in
the modulation of a centrally derived
coordination.
Funk,
G., I. I. Valenzuela, et al. (1997). "Energetic
consequences of coordinating wingbeat and
respiratory rhythms in birds." J Exp Biol 200(Pt
5): 915-20.
The coordination of ventilatory and
locomotor rhythms has been documented in many
birds and mammals. It has been suggested that
the physiological significance of such
coordination is a reduction in the cost of
ventilation which confers an energetic advantage
to the animal. We tested this hypothesis by
measuring the external work required to
ventilate birds mechanically during simulated
flight. Patterns of wing motion and breathing
were produced in which the relationship between
wing motion and breathing was in phase and out
of phase with the relationship seen during
normal flight. Differences between the energetic
costs of in-phase versus out-of-phase
synchronization were particularly large (26 %)
in instances where locomotion and respiration
frequency were synchronized at one breath per
wingbeat. The saving (9 %) obtained from
in-phase versus out-of-phase coordination at the
3:1 coordination ratio seen normally in
free-flying Canada geese was smaller but still
supported the hypothesis that there is a
significant net saving obtained from reducing
the mechanical interference between locomotion
and ventilation by locomotor­respiratory
coupling.
Morin, D. and D.
Viala (2002). "Coordinations of locomotor and
respiratory rhythms in vitro are critically
dependent on hindlimb sensory inputs." J
Neurosci 22(11): 4756-65. télécharger
PDF
A 1:1 coordination between locomotor and
respiratory movements has been described in
various mammalian species during fast
locomotion, and several mechanisms underlying
such interactions have been proposed. Here we
use an isolated brainstem-spinal cord
preparation of the neonatal rat to determine the
origin of this coupling, which could derive
either from a direct interaction between the
central locomotor- and respiratory-generating
networks themselves or from an indirect
influence via a peripheral mechanism. We
demonstrate that during fictive locomotion
induced by pharmacological activation of the
lumbar locomotor generators, a concomitant
increase in spontaneous respiratory rate occurs
without any evident form of phase coupling. In
contrast, respiratory motor activity can be
fully entrained (1:1 coupling) over a range of
periodic electrical stimulation applied to
low-threshold sensory pathways originating from
hindlimb muscles. Our results provide strong
support for the existence of pathways between
lumbar proprioceptive afferents, medullary
respiratory networks, and phrenic motoneurons
that could provide the basis of the
locomotor-respiratory coupling in many animals.
Thus a peripheral sensory system involved in a
well defined rhythmic motor function can be
responsible for the tight functional interaction
between two otherwise independent motor
behaviors.
Schomburg,
E. D., H. Steffens, et al. (2003). "Rhythmic
phrenic, intercostal and sympathetic activity in
relation to limb and trunk motor activity in
spinal cats." Neurosci Res 46(2):
229-40.
During L-DOPA-induced fictive spinal
locomotion rhythmic activities in nerves to
internal intercostal and external oblique
abdominal muscles and in phrenic and sympathetic
nerves were observed which were always
coordinated with locomotor activity in forelimb
and hindlimb muscle nerves. A periodicity with
longer lasting tonic phases could be induced by
cutaneous nerve stimulation or asphyxia. This
activity was observed in limb motor nerves as
well as in respiratory motor and sympathetic
nerves. A slow independent activity of the
phrenic and intercostal nerves or the
sympathetic nerves, which could be related to a
normal respiratory rhythm or independent
sympathetic rhythms was not observed. The
findings indicate that during fictive spinal
locomotion the activity of spinal rhythm
generators for locomotion also projects onto
respiratory and sympathetic spinal
neurones.
