Respiratory Physiology & Neurobiology最新文献

{"title":"Recovery of ventilatory and metabolic responses to hypoxia in neonatal rats after chronic hypoxia","authors":"Ryan W. Bavis,&nbsp;Darya I. Lee ,&nbsp;Annie C. Kinnally,&nbsp;Payton E. Buxton","doi":"10.1016/j.resp.2024.104317","DOIUrl":"10.1016/j.resp.2024.104317","url":null,"abstract":"<div><p>Chronic hypoxia (CH) during postnatal development attenuates the hypoxic ventilatory response (HVR) in mammals, but there are conflicting reports on whether this plasticity is permanent or reversible. This study tested the hypothesis that CH-induced respiratory plasticity is reversible in neonatal rats and investigated whether the initial plasticity or recovery differs between sexes. Rat pups were exposed to 3 d of normobaric CH (12 % O₂) beginning shortly after birth. Ventilation and metabolic CO₂ production were then measured in normoxia and during an acute hypoxic challenge (12 % O₂) immediately following CH and after 1, 4–5, and 7 d in room air. CH pups hyperventilated when returned to normoxia immediately following CH, but normoxic ventilation was similar to age-matched control rats within 7 d after return to room air. The early phase of the HVR (minute 1) was only blunted immediately following the CH exposure, while the late phase of the HVR (minute 15) remained blunted after 1 and 4–5 d in room air; recovery appeared complete by 7 d. However, when normalized to CO₂ production, the late phase of the hypoxic response recovered within only 1 d. The initial blunting of the HVR and subsequent recovery were similar in female and male rats. Carotid body responses to hypoxia (<em>in vitro</em>) were also normal in CH pups after approximately one week in room air. Collectively, these data indicate that ventilatory and metabolic responses to hypoxia recover rapidly in both female and male neonatal rats once normoxia is restored following CH.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":"329 ","pages":"Article 104317"},"PeriodicalIF":1.9,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142073755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lung function parameters are associated with acute mountain sickness and are improved at high and extreme altitude","authors":"Reto Reiser ,&nbsp;Anne-Kathrin Brill ,&nbsp;Christos T. Nakas ,&nbsp;Urs Hefti ,&nbsp;David Berger ,&nbsp;Eveline Perret Hoigné ,&nbsp;Hans-Joachim Kabitz ,&nbsp;Tobias M. Merz ,&nbsp;Jacqueline Pichler Hefti","doi":"10.1016/j.resp.2024.104318","DOIUrl":"10.1016/j.resp.2024.104318","url":null,"abstract":"<div><p>At altitude, factors such as decreased barometric pressure, low temperatures, and acclimatization might affect lung function.</p><p>The effects of exposure and acclimatization to high-altitude on lung function were assessed in 39 subjects by repetitive spirometry up to 6022 m during a high-altitude expedition. Subjects were classified depending on the occurrence of acute mountain sickness (AMS) and summit success to evaluate whether lung function relates to successful climb and risk of developing AMS.</p><p>Peak expiratory flow (PEF), forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) increased with progressive altitude (max. +20.2 %pred, +9.3 %pred, and +6.7 %pred, all p&lt;0.05). Only PEF improved with acclimatization (BC1 vs. BC2, +7.2 %pred, p=0.044). At altitude FEV1 (p=0.008) and PEF (p&lt;0.001) were lower in the AMS group.</p><p>The risk of developing AMS was associated with lower baseline PEF (p&lt;0.001) and longitudinal changes in PEF (p=0.008) and FEV1 (p&lt;0.001). Lung function was not related to summit success (7126 m). Improvement in PEF after acclimatization might indicate respiratory muscle adaptation.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":"330 ","pages":"Article 104318"},"PeriodicalIF":1.9,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142056403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Airway mechanics alters generation of cough motor pattern","authors":"Ivan Poliacek ,&nbsp;Marcel Veternik ,&nbsp;Lukas Martvon ,&nbsp;Zuzana Kotmanova ,&nbsp;Lucia Babalova ,&nbsp;Lucia Cibulkova ,&nbsp;Denisa Berikova ,&nbsp;Jana Plevkova ,&nbsp;Teresa Pitts ,&nbsp;Silvia Adzimova ,&nbsp;Michal Simera","doi":"10.1016/j.resp.2024.104315","DOIUrl":"10.1016/j.resp.2024.104315","url":null,"abstract":"<div><p>Effects of sequential increase in airway resistance: no, low (5 kPa.s/l), high (24 kPa.s/l), and complete block in the inspiratory or expiratory phase of mechanically induced cough on the cough motor pattern were studied in 16 anesthetized (pentobarbital) spontaneously breathing cats (3.70±0.15 kg, 11♂, 5♀). Esophageal pressure and electromyographic activities of the diaphragm during inspiration and abdominal muscles during expiration were analyzed. No significant changes in the number of coughs occurred. Inspiratory occlusion caused a prolongation of cough inspiratory phase, cough inspiratory diaphragm activity, and all cough-related activity. Inspiratory occlusion along with high resistance increased inspiratory esophageal pressure amplitude, total cough cycle duration and the time between maximum activity of the diaphragm and abdominal muscles. High expiratory resistance and occlusion resulted in increased cough expiratory esophageal pressure amplitude, a longer active portion of cough expiration, and cough abdominal activity. Expiratory occlusion also prolonged cough expiratory phase, all cough activity, and total cough cycle. Significantly increased airway resistance and occlusion induce secondary, in addition to mechanical, changes in cough by significantly modulating the generated cough motor pattern. A certain level of resistance appears to be successfully compensated, resulting in minimal changes in coughing characteristics, including expiratory airflow and the rising time of the airflow. Afferent feedback from the respiratory tract, particularly volume feedback, represents a significant factor in modulating cough, mainly under various pathological conditions in the respiratory system.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":"328 ","pages":"Article 104315"},"PeriodicalIF":1.9,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141917368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Difference in expiratory flow limitations development in normoxia and hypoxia in healthy individuals","authors":"Antoine Raberin ,&nbsp;Giorgio Manferdelli,&nbsp;Forrest Schorderet,&nbsp;Yannick Monnier,&nbsp;Ruben Tato Perez,&nbsp;Nicolas Bourdillon,&nbsp;Grégoire P. Millet","doi":"10.1016/j.resp.2024.104316","DOIUrl":"10.1016/j.resp.2024.104316","url":null,"abstract":"<div><p>The present study investigated the maintenance/repeatability of expiratory flow limitation (EFL) between normoxia and hypoxia.</p><p>Fifty-one healthy active individuals (27 men and 24 women) performed a lung function test and a maximal incremental cycling test in both normoxia and hypoxia (inspired oxygen fraction = 0.14) on two separate visits.</p><p>During exercise in normoxia, 28 participants exhibited EFL (55 %). In hypoxia, another cohort of 28 participants exhibited EFL. The two groups only partly overlapped.</p><p>Individuals with EFL only in normoxia reported lower maximal ventilation values in hypoxia than in normoxia (n=5; −13.5 ± 7.8 %) compared to their counterparts with EFL only in hypoxia (n=5; +6.7 ± 6.3 %) or without EFL (n=18; +5.1 ± 10.3 %) (p=0.004 and p&lt;0.001, respectively).</p><p>EFL development may be induced by different mechanisms in hypoxia vs. normoxia since the individuals who exhibited flow limitation were not the same between the two environmental conditions. This change seems influenced by the magnitude of the maximal ventilation change.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":"329 ","pages":"Article 104316"},"PeriodicalIF":1.9,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1569904824001095/pdfft?md5=8fb0a78dbac47078e7fb442521270ba6&pid=1-s2.0-S1569904824001095-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141996343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cardio-respiratory coupling and myocardial recovery in heart failure with reduced ejection fraction","authors":"Michiaki Nagai,&nbsp;Hallum Ewbank,&nbsp;Sunny S. Po,&nbsp;Tarun W. Dasari","doi":"10.1016/j.resp.2024.104313","DOIUrl":"10.1016/j.resp.2024.104313","url":null,"abstract":"<div><h3>Introduction</h3><p>The interaction between the cardiovascular and respiratory systems in healthy subjects is determined by the autonomic nervous system and reflected in respiratory sinus arrhythmia. Recently, another pattern of cardio-respiratory coupling (CRC) has been proposed linking synchronization of heart and respiratory system. However, CRC has not been studied precisely in heart failure (HF) with reduced ejection fraction (EF) (HFrEF) according to the myocardial recovery.</p></div><div><h3>Methods</h3><p>10-min resting electrocardiography measurements were performed in persistent HFrEF patients (n=40) who had a subsequent left ventricular EF (LVEF) of ≤ 40 %, HF with recovered EF patients (HFrecEF) (n=41) who had a subsequent LVEF of &gt; 40 % and healthy controls (n=40). Respiratory frequency, respiratory rate, CRC index, time-domain, frequency-domain and nonlinear heart rate variability indices were obtained using standardized software-Kubios™. CRC index was defined as respiratory high-frequency peak minus heart rate variability high-frequency peak.</p></div><div><h3>Results</h3><p>Respiratory rate was positively correlated with high-frequency (HF) peak (Hz) in both persistent HFrEF group (p&lt;0.001) and HFrecEF group (p&lt;0.001), while respiratory rate was negatively correlated with HF power (ms²) in the healthy controls (p&lt;0.05). CRC index was lowest in the persistent HFrEF group followed by HFrecEF and was high in healthy controls (0.008 vs 0.012 vs 0.056 Hz, p=0.03).</p></div><div><h3>Conclusion</h3><p>CRC index was lowest in patients with impaired myocardial recovery, which indicates that cardio-respiratory synchrony is stronger in persistent HFrEF. This may represent a higher HF peak (Hz)/lower HF power (ms²) and abnormal sympathovagal balance in persistent HFrEF group compared to healthy controls. Further work is underway to tests this hypothesis and determine the utility of CRC index in HF phenotypes and its utility as a potential biomarker of response with neuromodulation.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":"328 ","pages":"Article 104313"},"PeriodicalIF":1.9,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141913724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of positive allosteric modulation and orthosteric agonism of dopamine D2-like receptors on respiration in mouse models of Rett syndrome","authors":"Sebastian N. Maletz ,&nbsp;Brandon T. Reid ,&nbsp;David M. Baekey ,&nbsp;Jessica R. Whitaker-Fornek ,&nbsp;Jordan T. Bateman ,&nbsp;Keiko Arakawa ,&nbsp;John M. Bissonnette ,&nbsp;Erica S. Levitt","doi":"10.1016/j.resp.2024.104314","DOIUrl":"10.1016/j.resp.2024.104314","url":null,"abstract":"<div><p>Rett syndrome (RTT) is an autism spectrum disorder caused by loss-of-function mutations in the methyl-CPG-binding protein 2 (<em>Mecp2</em>) gene. Frequent apneas and irregular breathing are prevalent in RTT, and also occur in rodent models of the disorder, including <em>Mecp2</em>^Bird and <em>Mecp2</em>^R168X mice. Sarizotan, a serotonin 5-HT1a and dopamine D2-like receptor agonist, reduces the incidence of apneas and irregular breathing in mouse models of RTT (Abdala et al., 2014). Targeting the 5HT1a receptor alone also improves respiration in RTT mice (Levitt et al., 2013). However, the contribution of D2-like receptors in correcting these respiratory disturbances remains untested. PAOPA, a dopamine D2-like receptor positive allosteric modulator, and quinpirole, a dopamine D2-like receptor orthosteric agonist, were used in conjunction with whole-body plethysmography to evaluate whether activation of D2-like receptors is sufficient to improve breathing disturbances in female heterozygous <em>Mecp2</em>^Bird/+ and <em>Mecp2</em>^R168X/+ mice. PAOPA did not significantly change apnea incidence or irregularity score in RTT mice. PAOPA also had no effect on the ventilatory response to hypercapnia (7 % CO₂). In contrast, quinpirole reduced apnea incidence and irregularity scores and improved the hypercapnic ventilatory response in <em>Mecp2</em>^R168X/+ and <em>Mecp2</em>^Bird/+ mice, while also reducing respiratory rate. These results suggest that D2-like receptors could contribute to the positive effects of sarizotan in the correction of respiratory abnormalities in Rett syndrome. However, positive allosteric modulation of D2-like receptors alone was not sufficient to evoke these effects.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":"328 ","pages":"Article 104314"},"PeriodicalIF":1.9,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141907587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impaired diffusion at submaximal lung inflation in asthma and copd patients","authors":"Sylvia Verbanck ,&nbsp;Mike Hughes","doi":"10.1016/j.resp.2024.104304","DOIUrl":"10.1016/j.resp.2024.104304","url":null,"abstract":"<div><h3>Introduction</h3><p>Dissolved-phase ¹²⁹Xe MRI metrics suggest that gas diffusion may be more compromised at submaximal lung inflation compared to maximal inflation. We hypothesized that this diffusion deficit could be detected by comparing the carbon monoxide transfer coefficient (Kco) at submaximal lung inflation to that measured routinely at total lung capacity (TLC).</p></div><div><h3>Methods</h3><p>Asthma and COPD patients performed carbon monoxide diffusion tests, first at maximal lung inflation for routine Kco and alveolar volume VA and then, at a 30 % reduced inflation (redux; obtaining Kco_redux and VA_redux). At both inflations mixing efficiency was determined as VA/TLC and VA_redux/TLC_redux to examine a potential effect on Kco_redux/Kco behavior.</p></div><div><h3>Results</h3><p>In normal subjects (n=36), median Kco_redux/Kco amounted to 130 [IQR:122–136]% as expected for normal Kco recruitment response. However, 60 % of asthma patients (49/83) and 80 % of COPD patients (44/55) showed reduced Kco recruitment at submaximal inflation (Kco_redux/Kco&lt;122 %). In the asthma group, with otherwise normal routine Kco, Kco_redux/Kco was significantly correlated with RV/TLC ratio (r=-0.53;P&lt;0.001), but not with VA/TLC. In COPD patients, all with abnormal routine Kco, abnormal Kco_redux/Kco response occurred in those patients with lower FEV₁, higher RV/TLC and lower VA/TLC (P&lt;0.01 for all).</p></div><div><h3>Conclusion</h3><p>Sizeable portions of COPD and asthma patients showed a lack of normal Kco recruitment at submaximal lung inflation, related to high RV/TLC. In asthma, this was the case despite normal Kco at full lung inflation, suggesting that hyperinflation at lung volumes less than TLC affects the carbon monoxide diffusion rate constant by distorting pulmonary capillaries and alveolar–capillary membranes.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":"328 ","pages":"Article 104304"},"PeriodicalIF":1.9,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141890048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chloride intracellular channel 4 participates in the regulation of lipopolysaccharide-induced inflammatory responses in human bronchial epithelial cells","authors":"Jinhua Luo ,&nbsp;Jia Wang ,&nbsp;Huijun Liu ,&nbsp;Wang Jiang ,&nbsp;Lang Pan ,&nbsp;Wenjie Huang ,&nbsp;Caixia Liu ,&nbsp;Xiangping Qu ,&nbsp;Chi Liu ,&nbsp;Xiaoqun Qin ,&nbsp;Yang Xiang","doi":"10.1016/j.resp.2024.104303","DOIUrl":"10.1016/j.resp.2024.104303","url":null,"abstract":"<div><p>The airway epithelium is located at the interactional boundary between the external and internal environments of the organism and is often exposed to harmful environmental stimuli. Inflammatory response that occurs after airway epithelial stress is the basis of many lung and systemic diseases. Chloride intracellular channel 4 (CLIC4) is abundantly expressed in epithelial cells. The purpose of this study was to investigate whether CLIC4 is involved in the regulation of lipopolysaccharide (LPS)-induced inflammatory response in airway epithelial cells and to clarify its potential mechanism. Our results showed that LPS induced inflammatory response and decreased CLIC4 levels in vivo and in vitro. CLIC4 silencing aggravated the inflammatory response in epithelial cells, while overexpression of CLIC4 combined with LPS exposure significantly decreased the inflammatory response compared with cells exposed to LPS without CLIC4 overexpression. By labeling intracellular chloride ions with chloride fluorescent probe MQAE, we showed that CLIC4 mediated intracellular chloride ion-regulated LPS-induced cellular inflammatory response.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":"327 ","pages":"Article 104303"},"PeriodicalIF":1.9,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141639987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advancing cough research: Methodological insights into cough challenge in guinea pig models using double chamber vs whole-body plethysmography","authors":"Jana Plevkova ,&nbsp;Janka Jakusova ,&nbsp;Mariana Brozmanova ,&nbsp;Zuzana Biringerova ,&nbsp;Tomas Buday","doi":"10.1016/j.resp.2024.104302","DOIUrl":"10.1016/j.resp.2024.104302","url":null,"abstract":"<div><h3>Objective</h3><p>This study compares two methods of citric acid-induced cough in guinea pigs in whole-body plethysmography (WBP) and double chamber plethysmography (DCP) to evaluate their efficacy.</p></div><div><h3>Methods</h3><p>Sixteen specific pathogen-free (SPF) and sixteen conventionally-bred (CON) animals were exposed to 0.4 M citric acid aerosol. They underwent cough provocation using both DCP and WBP methods. The number of coughs and latency to the first cough were recorded and analysed using statistical methods to determine significant differences between the two techniques.</p></div><div><h3>Results</h3><p>WBP resulted in significantly higher cough counts (WBP vs. DCP: 13±9 vs 2±3 for SPF; 14±8 vs 5±5 for CON; p&lt;0.0001) and shorter latency (WBP vs. DCP: 59±6 s vs 159±14 s for SPF; 77±4 s vs 112±12 s for CON; p&lt;0.0001) compared to DCP in both groups.</p></div><div><h3>Conclusion</h3><p>Methodological differences substantially impact cough responses. WBP provides a more reliable and physiologically relevant methodology for cough assessment, suggesting the need for standardized protocols in cough research to enhance translational relevance.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":"327 ","pages":"Article 104302"},"PeriodicalIF":1.9,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141634338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cardiorespiratory failure induced by inhalation of aerosolized fentanyl in anesthetized rats","authors":"Jianguo Zhuang,&nbsp;Shan Shi,&nbsp;Fadi Xu","doi":"10.1016/j.resp.2024.104300","DOIUrl":"10.1016/j.resp.2024.104300","url":null,"abstract":"<div><p>Intravenous rapid injection of fentanyl causes respiratory depression (severe apneas), leading to sudden death, which constitutes the deadliest drug reaction among overdoses of synthetic opioids. Here we asked whether acute inhalation of overdose fentanyl would also result in similar respiratory failure and death. The anesthetized and spontaneously breathing rats with tracheal cannulation were exposed to aerosolized fentanyl at 100 mg/m³ (FNT_H) or 30 mg/m³ (FNT_L) for 10 min. Minute ventilation (V_E), electromyography (EMG) of the internal and external intercostal muscles and thyroarytenoid muscles (EMG_II, EMG_EI, and EMG_TA), heart rate and arterial blood pressure were recorded. During the exposure, FNT_H and FNT_L immediately triggered bradypnea (40 % reduction, p &lt; 0.05) with T_E prolonged and then gradually decreased V_E by 40 % (P &lt; 0.05) after a brief V_E recovery. The initial T_E prolongation (apneas) were characterized by the cessation of EMG_EI activity with enhanced tonic discharges of EMG_TA and EMG_II. After termination of the exposure, the cardiorespiratory responses to FNT_L returned to the baseline values 30 min later, while those to FNT_H were greatly exacerbated (P &lt; 0.05), leading to ventilatory and cardiac arrest occurred 16.4 ± 4.7 min and 19.3 ± 4.5 min respectively after the onset of FNT_H. The ventilatory arrest was featured by cessation of both EMG_EI and EMG_II and augmentation of tonic EMG_TA. Our results suggest that acute exposure to an overdose of fentanyl aerosol leads to death through initially inducing a brief central and upper airway obstructive apnea as well as chest wall rigidity followed by gradual severe hypoventilation, bradycardia and hypotension, and eventual cardiorespiratory arrest in anesthetized rats.</p></div>","PeriodicalId":20961,"journal":{"name":"Respiratory Physiology & Neurobiology","volume":"327 ","pages":"Article 104300"},"PeriodicalIF":1.9,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141620816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}