Carotid Body Inflammation: Role in Hypoxia and in the Anti-inflammatory Reflex

Physiology, Journal Year: 2021, Volume and Issue: 37(3), P. 128 - 140

Published: Dec. 6, 2021

Emergent evidence indicates that the carotid body (CB) chemoreceptor may sense systemic inflammatory molecules and is an afferent arm of anti-inflammatory reflex. Moreover, a proinflammatory milieu within CB involved in enhanced chemosensory responsiveness to oxygen following sustained intermittent hypoxia. In this review, we focus on physiopathological participation CBs diseases, such as sepsis

Language: Английский

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Effect of Acute Hypoxia on Cardiorespiratory Coherence in Male Runners

Frontiers in Physiology, Journal Year: 2020, Volume and Issue: 11

Published: June 30, 2020

Understanding the mechanisms of oxygen supply regulation, which involves respiratory and cardiovascular systems, during human adaptation to intense physical activity, accompanied by hypoxemia, is important for management a training process. The objectives study were investigate cardiorespiratory coherence changes in low-frequency band response hypoxic exposure verify dependence these upon sports qualification level athletes. Twenty male runners aged 17– 25 years exposed acute normobaric hypoxia (10% O2) 10 minutes. Respiration, gas exchange heart rate measured at baseline, after exposure. To evaluate coupling, squared was calculated based on 5 sec averaged time series rhythms. Based achieved over four experimental testing, athletes retrospectively divided into two groups, one with high (HLG, n = 10) other middle (MLG, 10). No differences anthropometric traits observed between groups. In pooled group, significantly increased (CRC) frequencies 0.030–0.045 Hz 0.075 Hz. hypoxia, consumption decreased HLG, carbon dioxide production ventilation MLG. At 0.070-0.080 CRC HLG higher compared Thus, highly qualified enhance intersystem integration hypoxia. This finding can be physiological sign prognosis runners.

Language: Английский

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Sleep loss effects on physiological and cognitive responses to systemic environmental hypoxia

Frontiers in Physiology, Journal Year: 2022, Volume and Issue: 13

Published: Dec. 12, 2022

In the course of their missions or training, alpinists, but also mountain combat forces and security services, professional miners, aircrew, aircraft glider pilots helicopter crews are regularly exposed to altitude without oxygen supplementation. At altitude, humans systemic environmental hypoxia induced by decrease in barometric pressure (<1,013 hPa) which decreases inspired partial (PIO 2 ), while fraction is constant (equal approximately 20.9%). Effects on occur gradually depend duration exposure level. From 1,500 m (response threshold), several adaptive responses offset effects hypoxia, involving respiratory cardiovascular systems, transport capacity blood. Fatigue cognitive sensory disorders usually observed from 2,500 (threshold prolonged hypoxia). Above 3,500 (the threshold for disorders), not completely compensated maladaptive individuals develop headache acute illness [Acute Mountain Sickness (AMS)]. The magnitude varies considerably between different physiological systems exhibits significant inter-individual variability. addition comorbidities, factors vulnerability still little known. They can be constitutive (genetic) circumstantial (sleep deprivation, fatigue, speed ascent.). particular, sleep loss, a condition that often encountered real-life settings, could have an impact hypoxia. this review, we report current state knowledge loss humans, with aim identifying possible consequences AMS risk cognition, as well value behavioral non-pharmacological countermeasures.

Language: Английский

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The muscle reflex and chemoreflex interaction: ventilatory implications for the exercising human

Journal of Applied Physiology, Journal Year: 2020, Volume and Issue: 129(4), P. 691 - 700

Published: Aug. 20, 2020

We examined the interactive influence of muscle reflex (MR) and chemoreflex (CR) on ventilatory response to exercise. Eleven healthy subjects (5 women/6 men) completed three bouts constant-load single-leg knee-extension exercise in a control trial an identical conducted with lumbar intrathecal fentanyl attenuate neural feedback from lower-limb group III/IV afferents. The during two trials was performed while breathing ambient air ([Formula: see text] ~97%, [Formula: text]~84 mmHg, ~32 pH ~7.39), or under normocapnic hypoxia ~79%, ~43 ~33 ~7.39) normoxic hypercapnia ~98%, ~105 ~50 ~7.26). During coactivation MR hypoxia-induced CR (O2-CR), minute ventilation (V̇e) tidal volume (VT) were significantly greater compared sum responses activation each alone; there no difference between observed summated terms frequency (fB; P = 0.4). hypercapnia-induced (CO2-CR), similar reflexes (P ≥ 0.1). Therefore, interaction O2-CR exerts hyperadditive effect V̇e VT additive fB, whereas CO2-CR is simply for all parameters. These findings reveal that MR:CR further augments hypoxia.NEW & NOTEWORTHY Although are recognized as independent mechanisms regulating exercise, implications resulting their remain unclear. quantified individual effects these revealed differential modes interaction. Importantly, amplifies hypoxemic conditions, highlighting potential mechanism optimizing arterial oxygenation physically active humans at high altitude.

Language: Английский

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The medullary serotonergic centres involved in cardiorespiratory control are disrupted by fetal growth restriction

The Journal of Physiology, Journal Year: 2023, Volume and Issue: 602(21), P. 5923 - 5941

Published: Aug. 28, 2023

Abstract Fetal growth restriction (FGR) is associated with cardiovascular and respiratory complications after birth beyond. Despite research showing a range of neurological changes following FGR, little known about how FGR affects the brainstem cardiorespiratory control centres. The primary neurons that release serotonin reside in centres may be affected by FGR. At two time points last trimester sheep brain development, 110 127 days gestation (0.74 0.86 gestation), we assessed histopathological alterations pons medulla early‐onset versus fetal sheep. cohort were hypoxaemic asymmetrically restricted. Compared to controls, fetuses exhibited signs neuropathology, including elevated cell death reduced proliferation, grey white matter deficits, evidence oxidative stress neuroinflammation. pathology was predominantly observed medullary raphé nuclei, hypoglossal nucleus, nucleus ambiguous, solitary tract tract. groups showed imbalanced 1A receptor abundance despite increased staining within vascular regions placentomes collected from fetuses. Our findings demonstrate both early adaptive neuropathology response placental insufficiency. image Key Early‐onset induced sheep, resulting chronic hypoxaemia. Growth‐restricted exhibit persistent characterised disrupted proliferation neuronal number critical responsible for regulation functions. Elevated inflammation suggest potential mechanisms contributing neuropathological changes. Both levels 5‐HT found impaired

Language: Английский

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TRPM7 channels regulate breathing during sleep in obesity by acting peripherally in the carotid bodies

The Journal of Physiology, Journal Year: 2022, Volume and Issue: 600(23), P. 5145 - 5162

Published: Oct. 10, 2022

Abstract Sleep‐disordered breathing (SDB) affects over 50% of obese individuals. Exaggerated hypoxic chemoreflex is a cardinal trait SDB in obesity. We have shown that leptin acts the carotid bodies (CB) to augment and activates transient receptor potential melastatin 7 (TRPM7) channel. However, effect leptin‐TRPM7 signalling CB on has not been characterized diet‐induced obesity (DIO). hypothesized via TRPM7 increase leading DIO mice were implanted with EEG/EMG electrodes transfected Lepr b short hairpin RNA (shRNA) or Trpm7 shRNA vs . control area bilaterally. Mice underwent full‐polysomnography metabolic studies at baseline after transfection. Ventilatory responses hypoxia hypercapnia assessed during wakefulness. upregulated their promoters demethylated mice. knockdown did significantly affect ventilation. Trpm stimulated sleep normoxia. These effects driven by changes chemosensitivity metabolism. Under sustained hypoxia, augmented ventilation sleep, but decreased oxyhaemoglobin saturation. conclude suppression improved sleep‐related hypoventilation respiratory channels are independent leptin. could be therapeutic target for treatment obesity‐related SDB. image Key points The axis may play an important role pathogenesis sleep‐disordered breathing. regulate acting peripherally bodies. Suppression improves obesity‐induced Pharmacological blockade therapy

Language: Английский

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Cardiovascular Physiology

Published: June 21, 2024

The principal function of the cardiovascular system is to circulate fluid (i.e., blood and lymph) throughout body. In animals, depends on a normally functioning heart, vessels, volume, lymphatic deliver oxygen, remove waste products, maintain homeostatic control body's temperature, pH, cellular environment. Since flow responsible for uptake, delivery, elimination all drugs including anesthetic drugs, functional appreciation anatomy circulatory dynamics are required safe practice. This chapter reviews physiology systems mammals summarizes general effects anesthesia their function.

Language: Английский

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Brain Circuitry for Arousal from Apnea

Cold Spring Harbor Symposia on Quantitative Biology, Journal Year: 2018, Volume and Issue: 83, P. 63 - 69

Published: Jan. 1, 2018

We wanted to understand the brain circuitry that awakens individual when there is elevated CO2 or low O2 (e.g., during sleep apnea asphyxia). The sensory signals for high and all converge on parabrachial nucleus (PB) of pons, which contains neurons project forebrain. So, we first deleted vesicular glutamate transporter 2, necessary load into synaptic vesicles, from in PB, showed this prevents awakening then PB express calcitonin gene-related peptide (CGRP) show cFos staining Using CGRP-Cre-ER mice, expressed inhibitory opsin archaerhodopsin just PBCGRP neurons. Photoinhibition effectively prevented CO2, as did photoinhibition their terminals basal forebrain, amygdala, lateral hypothalamus. are a key mediator wakening response apnea.

Language: Английский

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The logic behind neural control of breathing pattern

Scientific Reports, Journal Year: 2019, Volume and Issue: 9(1)

Published: June 24, 2019

The respiratory rhythm generator is spectacular in its ability to support a wide range of activities and adapt changing environmental conditions, yet operating mechanisms remain elusive. We show how selective control inspiration expiration times can be achieved new representation the neural system (called Boolean network). framework enables us predict behavior networks based on properties neurons, not their values. Hence, it reveals logic behind that breathing pattern. Our network mimics many features seen such as transition from 3-phase 2-phase 1-phase rhythm, providing novel insights testable predictions.

Language: Английский

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A computational model of the respiratory network challenged and optimized by data from optogenetic manipulation of glycinergic neurons

Neuroscience, Journal Year: 2017, Volume and Issue: 347, P. 111 - 122

Published: Feb. 13, 2017

Language: Английский

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