Cardiorespiratory interaction

2015 ◽  
Vol 32 (6) ◽  
pp. 374-375
Author(s):  
Tim Felton ◽  
Malachy Columb
Keyword(s):  
Cardiorespiratory Interaction

Endogenous Acetylcholine and Nicotine Activation Enhances GABAergic and Glycinergic Inputs to Cardiac Vagal Neurons

2003 ◽  
Vol 89 (5) ◽  
pp. 2473-2481 ◽  
Author(s):  
Jijiang Wang ◽  
Xin Wang ◽  
Mustapha Irnaten ◽  
Priya Venkatesan ◽  
Cory Evans ◽  
...  
Keyword(s):  
Nicotinic Receptors ◽  
Nucleus Ambiguus ◽  
Cholinergic Activity ◽  
Fluorescent Tracer ◽  
Sinus Arrhythmia ◽  
Synaptic Inputs ◽  
Cardiorespiratory Interaction ◽  
Parasympathetic Neurons ◽  
Glycinergic Neurotransmission

The heart slows during expiration and heart rate increases during inspiration. This cardiorespiratory interaction is thought to occur by increased inhibitory synaptic events to cardiac vagal neurons during inspiration. Since cholinergic receptors have been suggested to be involved in this cardiorespiratory interaction, we tested whether endogenous cholinergic activity modulates GABAergic and glycinergic neurotransmission to cardiac vagal neurons in the nucleus ambiguus, whether nicotine can mimic this facilitation, and we examined the nicotinic receptors involved. Cardiac vagal neurons in the rat were labeled with a retrograde fluorescent tracer and studied in an in vitro slice using patch-clamp techniques. Application of neostigmine (10 μM), an acetylcholinerase inhibitor, significantly increased the frequency of both GABAergic and glycinergic inhibitory postsynaptic currents (IPSCs) in cardiac vagal neurons. Exogenous application of nicotine increased the frequency and amplitude of both GABAergic and glycinergic IPSCs. The nicotinic facilitation of both GABAergic and glycinergic IPSCs were insensitive to 100 nM α-bungarotoxin but were abolished by dihydro-β-erythrodine (DHβE) at a concentration (3 μM) specific for α4β2 nicotinic receptors. In the presence of TTX, nicotine increased the frequency of GABAergic and glycinergic miniature synaptic events, which were also abolished by DHβE (3 μM). This work demonstrates that there is endogenous cholinergic facilitation of GABAergic and glycinergic synaptic inputs to cardiac vagal neurons, and activation of α4β2 nicotinic receptors at presynaptic terminals facilitates GABAergic and glycinergic neurotransmission to cardiac vagal neurons. Nicotinic facilitation of inhibitory neurotransmission to premotor cardiac parasympathetic neurons may be involved in generating respiratory sinus arrhythmia.

scholarly journals Phase coupling in the cardiorespiratory interaction

2008 ◽  
Vol 2 (1) ◽  
pp. 48-54 ◽  
Author(s):  
A. Bahraminasab ◽  
D. Kenwright ◽  
A. Stefanovska ◽  
F. Ghasemi ◽  
P.V.E. McClintock
Keyword(s):  
Phase Coupling ◽  
Cardiorespiratory Interaction

Directionality of coupling of physiological subsystems: age-related changes of cardiorespiratory interaction during different sleep stages in babies

2003 ◽  
Vol 285 (6) ◽  
pp. R1395-R1401 ◽  
Author(s):  
Ralf Mrowka ◽  
Laura Cimponeriu ◽  
Andreas Patzak ◽  
Michael G. Rosenblum
Keyword(s):  
Mutual Influence ◽  
Sleep Stage ◽  
Heart Rhythm ◽  
Sleep Stages ◽  
Oscillatory Systems ◽  
Strength Of Interaction ◽  
Age Related ◽  
Cardiorespiratory Interaction ◽  
The Central Nervous System ◽  
Cardiovascular Rhythms

Activity of many physiological subsystems has a well-expressed rhythmic character. Often, a dependency between physiological rhythms is established due to interaction between the corresponding subsystems. Traditional methods of data analysis allow one to quantify the strength of interaction but not the causal interrelation that is indispensable for understanding the mechanisms of interaction. Here we present a recently developed method for quantification of coupling direction and apply it to an important problem. Namely, we study the mutual influence of respiratory and cardiovascular rhythms in healthy newborns within the first 6 mo of life in quiet and active sleep. We find an age-related change of the coupling direction: the interaction is nearly symmetric during the first days and becomes practically unidirectional (from respiration to heart rhythm) at the age of 6 mo. Next, we show that the direction of interaction is mainly determined by respiratory frequency. If the latter is less than ≈0.6 Hz, the interaction occurs dominantly from respiration to heart. With higher respiratory frequencies that only occur at very young ages, the dominating direction is less pronounced or even abolished. The observed dependencies are not related to sleep stage, suggesting that the coupling direction is determined by system-inherent dynamical processes, rather than by functional modulations. The directional analysis may be applied to other interacting narrow band oscillatory systems, e.g., in the central nervous system. Thus it is an important step forward in revealing and understanding causal mechanisms of interactions.

NEUROCARDIAC-CARDIORESPIRATORY INTERACTION OF HEART-BRAIN MAILUNS SYNCHRONY AT DEEP ZEN MEDITATION

2016 ◽  
Vol 28 (06) ◽  
pp. 1650039
Author(s):  
Pei-Chen Lo ◽  
Wu Jue Miao Tian
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Low Frequency ◽  
Transition Process ◽  
Total Power ◽  
Sinus Arrhythmia ◽  
Respiration Rhythm ◽  
Scientific Hypothesis ◽  
Cardiorespiratory Interaction ◽  
Electrical Impulses

Innovatively new behaviors of heart rate variability caused by special heart-transition process were observed in the long-term, well-experienced Zen practitioners while practicing the heart-to-heart imprint sealing (HHIS) Zen meditation. HHIS Zen practice involves specific neurocardiac-cardiorespiratory interaction while on the way of realizing the heart-dominant, detached brain. Results of analyzing the electrocardiogram and respiratory signals of 10 experienced practitioners reveal several distinctive characteristics: (1) remarkably linear correlation between standard deviation of the normal R-to-R intervals, SDNN, and total power in very-low-frequency (VLF, 0.0033–0.04[Formula: see text]Hz) band of power spectrum of the heart-rate sequence, (2) time-varying VLF power dominating over the low-frequency and high-frequency power in heart rate variability (HRV) variations, (3) intermittent transition into slowly, deeply abdominal respiration inducing a boost of heart rates, (4) heart-rate baseline slowly fluctuating at 0.005–0.0067[Formula: see text]Hz, about 1.5–2 cycles in 5-min period, and (5) remarkable respiratory sinus arrhythmia (RSA) synchrony between heart rate and respiration rhythm. This paper proposes a rational scientific hypothesis for the neurocardiac-cardiorespiratory mechanism. The unique scheme of HHIS Zen meditation involves the spiritual-qi concentration and refinement for pinpointing into the particular energy centers, mailuns. Ignition by a subtle, deepest abdominal respiration, electrical impulses rapidly transmit from solar plexus to branchial plexuses to activate unique heart-transition process. Simultaneously, another branch streams upward the spinal cord to cervical plexus and brainstem that effectively harmonizes neurocardiac interactions. To investigate the underlying behaviors, time-domain and frequency-domain HRV based on continuous wavelet transform were employed.

Dynamic cardiorespiratory interaction during head-up tilt-mediated presyncope

2004 ◽  
Vol 287 (6) ◽  
pp. H2510-H2517 ◽  
Author(s):  
S. Krishnamurthy ◽  
X. Wang ◽  
D. Bhakta ◽  
E. Bruce ◽  
J. Evans ◽  
...  
Keyword(s):  
Transfer Functions ◽  
Cerebral Blood Flow Velocity ◽  
Cerebral Hemodynamics ◽  
Frequency Region ◽  
Cardiorespiratory Interaction ◽  
Head Up Tilt ◽  
Unexplained Syncope ◽  
End Tidal ◽  
The Relationship ◽  
Reactivity Change

In 28 healthy adults, we compared the dynamic interaction between respiration and cerebral autoregulation in 2 groups of subjects: those who did and did not develop presyncopal symptoms during 70° passive head-up tilt (HUT), i.e., nonpresyncopal (23 subjects) and presyncopal (5 subjects). Airflow, CO2, cerebral blood flow velocity (CBF), ECG, and blood pressure (BP) were recorded. To determine whether influences of mean BP (MBP) and systolic SP (SBP) on CBF were altered in presyncopal subjects, coherencies and transfer functions between these variables and mean and peak CBF (CBFm and CBFp) were estimated. To determine the influence of end-tidal CO2 (ETco2) on CBF, the relative CO2 reactivity (%change in CBFm per mmHg change in ETco2) was calculated. We found that in presyncopal subjects before symptoms during HUT, coherence between SBP and CBFp was higher ( P = 0.02) and gains of transfer functions between BP (MBP and SBP) and CBFm were larger (MBP, P = 0.01; SBP, P = 0.01) in the respiratory frequency region. In the last 3 min before presyncope, presyncopals had a reduced relative CO2 reactivity ( P = 0.005), likely a consequence of the larger decrease in ETco2. We hypothesize that the CO2-mediated increase in resistance attenuates autoregulation such that the relationship between systemic and cerebral hemodynamics is enhanced. Our results suggest that an altered cardiorespiratory interaction involving cerebral hemodynamics may contribute in the cascade of events during tilt that culminate in unexplained syncope.

scholarly journals Breath-by-breath analysis of cardiorespiratory interaction for quantifying developmental maturity in premature infants

2012 ◽  
Vol 112 (5) ◽  
pp. 859-867 ◽  
Author(s):  
Matthew T. Clark ◽  
Craig G. Rusin ◽  
John L. Hudson ◽  
Hoshik Lee ◽  
John B. Delos ◽  
...  
Keyword(s):  
Intensive Care ◽  
Probability Density ◽  
Respiratory Sinus Arrhythmia ◽  
Neonatal Intensive Care ◽  
Breath Analysis ◽  
Underlying Mechanism ◽  
Sinus Arrhythmia ◽  
Rate Of Increase ◽  
Cardiorespiratory Interaction ◽  
Developmental Maturity

In healthy neonates, connections between the heart and lungs through brain stem chemosensory pathways and the autonomic nervous system result in cardiorespiratory synchronization. This interdependence between cardiac and respiratory dynamics can be difficult to measure because of intermittent signal quality in intensive care settings and variability of heart and breathing rates. We employed a phase-based measure suggested by Schäfer and coworkers (Schäfer C, Rosenblum MG, Kurths J, Abel HH. Nature 392: 239–240, 1998) to obtain a breath-by-breath analysis of cardiorespiratory interaction. This measure of cardiorespiratory interaction does not distinguish between cardiac control of respiration associated with cardioventilatory coupling and respiratory influences on the heart rate associated with respiratory sinus arrhythmia. We calculated, in sliding 4-min windows, the probability density of heartbeats as a function of the concurrent phase of the respiratory cycle. Probability density functions whose Shannon entropy had a <0.1% chance of occurring from random numbers were classified as exhibiting interaction. In this way, we analyzed 18 infant-years of data from 1,202 patients in the Neonatal Intensive Care Unit at University of Virginia. We found evidence of interaction in 3.3 patient-years of data (18%). Cardiorespiratory interaction increased several-fold with postnatal development, but, surprisingly, the rate of increase was not affected by gestational age at birth. We find evidence for moderate correspondence between this measure of cardiorespiratory interaction and cardioventilatory coupling and no evidence for respiratory sinus arrhythmia, leading to the need for further investigation of the underlying mechanism. Such continuous measures of physiological interaction may serve to gauge developmental maturity in neonatal intensive care patients and prove useful in decisions about incipient illness and about hospital discharge.

Identification of coupling direction: Application to cardiorespiratory interaction

2002 ◽  
Vol 65 (4) ◽  
Author(s):  
Michael G. Rosenblum ◽  
Laura Cimponeriu ◽  
Anastasios Bezerianos ◽  
Andreas Patzak ◽  
Ralf Mrowka
Keyword(s):  
Cardiorespiratory Interaction
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