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1.
Neuron ; 109(7): 1137-1149.e5, 2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-33600762

RESUMO

Progressive loss of dopamine inputs in Parkinson's disease leads to imbalances in coordinated signaling of dopamine and acetylcholine (ACh) in the striatum, which is thought to contribute to parkinsonian motor symptoms. As reciprocal interactions between dopamine inputs and cholinergic interneurons (ChIs) control striatal dopamine and ACh transmission, we examined how partial dopamine depletion in an early-stage mouse model for Parkinson's disease alters nigral regulation of cholinergic activity. We found region-specific alterations in how remaining dopamine inputs regulate cholinergic excitability that differ between the dorsomedial (DMS) and dorsolateral (DLS) striatum. Specifically, we found that dopamine depletion downregulates metabotropic glutamate receptors (mGluR1) on DLS ChIs at synapses where dopamine inputs co-release glutamate, abolishing the ability of dopamine inputs to drive burst firing. This loss underlies parkinsonian motor impairments, as viral rescue of mGluR1 signaling in DLS ChIs was sufficient to restore circuit function and attenuate motor deficits in early-stage parkinsonian mice.


Assuntos
Interneurônios , Transtornos Motores/fisiopatologia , Sistema Nervoso Parassimpático/fisiopatologia , Transtornos Parkinsonianos/fisiopatologia , Substância Negra/fisiopatologia , Acetilcolina/metabolismo , Animais , Comportamento Animal , Dopamina/metabolismo , Feminino , Ácido Glutâmico/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neostriado/metabolismo , Neostriado/fisiopatologia , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/psicologia , Receptores de AMPA/biossíntese , Receptores de AMPA/genética , Sinapses/metabolismo , Transmissão Sináptica
2.
Artigo em Inglês | MEDLINE | ID: mdl-33375223

RESUMO

Sudden cardiac death (SCD) is the leading type of line-of-duty death among firefighters. An inability to restore parasympathetic nervous system (PSNS) control after activity is associated with SCD. Post-exercise heart rate recovery (HRR) provides unique insight into reactivation of the PSNS. Thus, the purpose of this study was to examine longitudinal changes in HRR responses of 25 male firefighter recruits. HR data were collected after submaximal exercise at week 1 (W1), week 6 (W6), and week 15 (W15) of their training at an academy. Percent maximal heart rate (%MHR) measures were computed at each HRR time point (%MHR0, %MHR15, %MHR30, %MHR45, %MHR60, %MHR120, %MHR180) and absolute HRR values were calculated at 30 s (ΔHRR30), 60 s (ΔHRR60), 120 s (ΔHRR120), and 180 s (ΔHRR180). After controlling for age and percent body fat, there was no statistically significant interaction between Week × HRR (p = 0.730), and there were no changes in ΔHRR30, ΔHRR60, and ΔHRR120, and ΔHRR180 indices across time. However, %MHR at W6 and W15 was significantly lower than %MHR at W1 at every HRR time point (ps < 0.001). Therefore, although the firefighter recruit training academy elicited positive training adaptations, changes in PSNS reactivation after submaximal activity were not identified.


Assuntos
Bombeiros , Frequência Cardíaca , Sistema Nervoso Parassimpático/fisiopatologia , Condicionamento Físico Humano , Adaptação Fisiológica , Adulto , Estudos de Coortes , Exercício Físico , Humanos , Masculino , Pessoa de Meia-Idade
3.
Lancet Digit Health ; 2(12): e650-e657, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33328029

RESUMO

BACKGROUND: Heart rate variability, or the variation in the time interval between consecutive heart beats, is a non-invasive dynamic metric of the autonomic nervous system and an independent risk factor for cardiovascular death. Consumer wrist-worn tracking devices using photoplethysmography, such as Fitbit, now provide the unique potential of continuously measuring surrogates of sympathetic and parasympathetic nervous system activity through the analysis of interbeat intervals. We aimed to leverage wrist-worn trackers to derive and describe diverse measures of cardiac autonomic function among Fitbit device users. METHODS: In this cross-sectional study, we collected interbeat interval data that are sent to a central database from Fitbit devices during a randomly selected 24 h period. Age, sex, body-mass index, and steps per day in the 90 days preceding the measurement were extracted. Interbeat interval data were cleaned and heart rate variability features were computed. We analysed heart rate variability metrics across the time (measured via the root mean square of successive RR interval differences [RMSSD] and SD of the RR interval [SDRR]), frequency (measured by high-frequency and low-frequency power), and graphical (measured by Poincare plots) domains. We considered 5 min windows for the time and frequency domain metrics and 60 min measurements for graphical domain metrics. Data from participants were analysed to establish the correlation between heart rate variability metrics and age, sex, time of day, and physical activity. We also determined benchmarks for heart rate variability (HRV) metrics among the users. FINDINGS: We included data from 8 203 261 Fitbit users, collected on Sept 1, 2018. HRV metrics decrease with age, and parasympathetic function declines faster than sympathetic function. We observe a strong diurnal variation in the heart rate variability. SDRR, low-frequency power, and Poincare S2 show a significant variation with sex, whereas such a difference is not seen with RMSSD, high-frequency power, and Poincare S1. For males, when measured from 0600 h to 0700 h, the mean low-frequency power decreased by a factor of 66·5% and high-frequency power decreased by a factor of 82·0% from the age of 20 years to 60 years. For females, the equivalent factors were 69·3% and 80·9%, respectively. Comparing low-frequency power between males and females at the ages of 40-41 years, measured from 0600 h to 0700 h, we found excess power in males, with a Cohen's d effect size of 0·33. For high-frequency power, the equivalent effect size was -0·04. Increased daily physical activity, across age and sex, was highly correlated with improvement in diverse measures of heart rate variability in a dose-dependent manner. We provide benchmark tables for RMSSD, SDRR, high and low frequency powers, and Poincare S1 and S2, separately for different ages and sex and computed at two times of the day. INTERPRETATION: Diverse metrics of cardiac autonomic health can be derived from wrist-worn trackers. Empirical distributions of heart rate variability can potentially be used as a framework for individual-level interpretation. Increased physical activity might yield improvement in heart rate variability and requires prospective trials for confirmation. FUNDING: Fitbit.


Assuntos
Doenças Cardiovasculares , Frequência Cardíaca , Monitorização Ambulatorial/métodos , Sistema Nervoso Parassimpático , Sistema Nervoso Simpático , Telemedicina/métodos , Adolescente , Adulto , Fatores Etários , Idoso , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/fisiopatologia , Estudos Transversais , Exercício Físico/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistema Nervoso Parassimpático/fisiopatologia , Fotopletismografia/métodos , Estudos Prospectivos , Fatores Sexuais , Sistema Nervoso Simpático/fisiopatologia , Dispositivos Eletrônicos Vestíveis , Adulto Jovem
4.
ACS Chem Neurosci ; 11(14): 2048-2050, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32614178

RESUMO

In COVID-19, lung manifestations present as a slowly evolving pneumonia with insidious early onset interstitial pulmonary edema that undergoes acute exacerbation in the late stages and microvascular thrombosis. Currently, these manifestations are considered to be only consequences of pulmonary SARS-CoV-2 virus infection. We are proposing a new hypothesis that neurogenic insult may also play a major role in the pathogenesis of these manifestations. SARS-CoV-2 mediated inflammation of the nucleus tractus solitarius (NTS) may play a role in the acute exacerbation of pulmonary edema and microvascular clotting in COVID-19 patients.


Assuntos
Infecções por Coronavirus/fisiopatologia , Hipotensão/fisiopatologia , Pulmão/irrigação sanguínea , Microvasos/fisiopatologia , Pneumonia Viral/fisiopatologia , Edema Pulmonar/fisiopatologia , Núcleo Solitário/fisiopatologia , Trombose/fisiopatologia , Betacoronavirus , Permeabilidade Capilar/fisiologia , Infecções por Coronavirus/imunologia , Síndrome da Liberação de Citocina/imunologia , Síndrome da Liberação de Citocina/fisiopatologia , Nervo Facial , Nervo Glossofaríngeo , Humanos , Inflamação , Pulmão/imunologia , Microvasos/imunologia , Pandemias , Sistema Nervoso Parassimpático/fisiopatologia , Pneumonia Viral/imunologia , Edema Pulmonar/imunologia , Núcleo Solitário/imunologia , Nervo Vago , Vasoconstrição
5.
Cardiovasc Ther ; 2020: 1321782, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32695226

RESUMO

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease associated with elevated prevalence of comorbidities, especially metabolic and cardiovascular diseases. We used a tool called Heart Rate Variability (HRV) in order to assess the correlation between HS and alterations of the sympathetic-vagal equilibrium in the autonomic cardiovascular regulation system. We found increased sympathetic activity, associated with a higher risk of cardiovascular disease. HS, according to our results, is an independent cardiovascular risk factor.


Assuntos
Doenças Cardiovasculares/etiologia , Frequência Cardíaca , Coração/inervação , Hidradenite Supurativa/complicações , Sistema Nervoso Parassimpático/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Adolescente , Adulto , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/fisiopatologia , Feminino , Hidradenite Supurativa/diagnóstico , Hidradenite Supurativa/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco , Adulto Jovem
6.
Am J Physiol Regul Integr Comp Physiol ; 318(5): R940-R949, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32209022

RESUMO

We examined the relationship between hemodynamics in the three major salivary glands and salivary secretion in urethane-anesthetized and sympathectomized type 2 diabetic and nondiabetic rats via laser speckle imaging and by collecting the saliva. Lingual nerve stimulation elicited rapid increases in glandular blood flow and induced salivary secretion from the three glands in both diabetic and nondiabetic rats. In the parotid gland, the magnitude of blood flow increase and salivary secretion was significantly lower in the diabetic rats when compared with the nondiabetic rats; however, this was not observed in the other glands. Although the intravenous administration of acetylcholine increased blood flow in the parotid gland in a dose-dependent manner, the response was significantly lower in the diabetic rats when compared with the nondiabetic rats. Similarly, mRNA expression levels of M1 and M3 muscarinic acetylcholine receptors in the parotid gland were relatively lower in the diabetic rats compared with the nondiabetic rats. Our results indicate that type 2 diabetes impairs parasympathetic vasodilation and salivary secretion in the parotid gland and suggest that disturbances in the cholinergic vasodilator pathway may contribute to the underlying mechanisms involved in the disruption of parasympathetic nerve-mediated glandular vasodilation.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Neuropatias Diabéticas/fisiopatologia , Sistema Nervoso Parassimpático/fisiopatologia , Glândula Parótida/irrigação sanguínea , Glândula Parótida/fisiopatologia , Salivação , Vasodilatação , Xerostomia/fisiopatologia , Animais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Neuropatias Diabéticas/etiologia , Neuropatias Diabéticas/genética , Neuropatias Diabéticas/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Masculino , Glândula Parótida/metabolismo , Ratos Endogâmicos OLETF , Receptor Muscarínico M1/genética , Receptor Muscarínico M1/metabolismo , Receptor Muscarínico M3/genética , Receptor Muscarínico M3/metabolismo , Xerostomia/etiologia , Xerostomia/genética , Xerostomia/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-32050580

RESUMO

Background: Medical residency is a time of high stress and long working hours, which increase the risk of cardiovascular disease. This study aimed to investigate the autonomic modulation of resident physicians throughout the on-call duty cycle. Methods: Spectral analysis of heart rate variability (HRV) was used to compute cardiac parasympathetic modulation (high-frequency power, HF) and cardiac sympathetic modulation (normalized low-frequency power, LF%, and the ratio of LF and HF, LF/HF) of 18 residents for a consecutive 4-day cycle. Results: Male residents show reduced cardiac sympathetic modulation (i.e., higher LF/HF and LF%) than the female interns. Medical residents' cardiac parasympathetic modulation (i.e., HF) significantly increased on the first and the second post-call day compared with the pre-call day. In contrast, LF% was significantly decreased on the first and the second post-call day compared with the pre-call day. Similarly, LF/HF was significantly decreased on the second post-call day compared with the pre-call day. LF/HF significantly decreased on the first post-call day and on the second post-call day from on-call duty. Conclusion: The guideline that limits workweeks to 80 h and shifts to 28 h resulted in reduced sympathetic modulation and increased parasympathetic modulation during the two days following on-call duty.


Assuntos
Sistema Nervoso Autônomo , Doenças Cardiovasculares , Frequência Cardíaca/fisiologia , Coração/fisiopatologia , Internato e Residência , Sistema Nervoso Parassimpático/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Ritmo Circadiano , Feminino , Humanos , Masculino , Carga de Trabalho
8.
J Abnorm Psychol ; 129(3): 237-247, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32077707

RESUMO

The valine66methionine (Val66Met) polymorphism (rs6265) of the brain-derived neurotrophic factor (BDNF) gene has been shown to influence autonomic arousal pathways, which in turn predict elevated syndromal anxiety in healthy humans. We examined whether the BDNF variant is associated with an increased risk of generalized anxiety disorder (GAD), one of the most prevalent anxiety disorders, through altering parasympathetic stress/relaxation reactivity. A total of 2,250 Han Chinese adults (750 GAD patients and 1,500 healthy controls) were included in the genotyping. High-frequency heart rate variability, an index of vagal (parasympathetic) activity, was measured during the supine-standing-supine test (5 min in each position); vagal withdrawal and vagal activation were calculated as baseline supine minus standing and recovery supine minus standing, respectively. Analysis of healthy participants indicated that Val/Val homozygotes displayed significantly blunted vagal withdrawal and vagal activation compared with Met allele carriers. After analyzing the entire sample, these effects remained significant. Furthermore, both attenuated vagal response patterns were found to be significantly associated with a higher incidence of GAD. Lastly, the path analysis identified a significant indirect effect of BDNF on the risk of GAD via diminishing vagal response to either orthostatic stress or supine relaxation. Even when further testing the subsample comprising only comorbidity- and medication-free GAD patients and healthy controls to minimize the confounding bias, the results still remained. Our findings demonstrate that individuals carrying the BDNF Val/Val genotype, compared to Met-carriers, may be at higher risk of GAD due to blunted vagal reactivity in response to both stress and relaxation. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Transtornos de Ansiedade/genética , Ansiedade/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Genótipo , Sistema Nervoso Parassimpático/fisiopatologia , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Ansiedade/fisiopatologia , Transtornos de Ansiedade/fisiopatologia , Nível de Alerta/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Nervo Vago/fisiopatologia
9.
Epilepsia ; 61(3): 572-588, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32030748

RESUMO

OBJECTIVE: Immediately preceding sudden unexpected death in epilepsy (SUDEP), patients experienced a final generalized tonic-clonic seizure (GTCS), rapid ventilation, apnea, bradycardia, terminal apnea, and asystole. Whether a progressive pathophysiology develops and increases risk of SUDEP remains unknown. Here, we determined (a) heart rate, respiratory rate, and blood oxygen saturation (SaO2 ) in low-risk and high-risk knockout (KO) mice; and (b) whether blocking receptors for orexin, a cardiorespiratory neuromodulator, influences cardiorespiratory function mice or longevity in high-risk KO mice. METHODS: Heart rate and SaO2 were determined noninvasively with ECGenie and pulse oximetry. Respiration was determined with noninvasive airway mechanics technology. The role of orexin was determined within subject following acute treatment with a dual orexin receptor antagonist (DORA, 100 mg/kg). The number of orexin neurons in the lateral hypothalamus was determined with immunohistochemistry. RESULTS: Intermittent bradycardia was more prevalent in high-risk KO mice, an effect that may be the result of increased parasympathetic drive. High-risk KO mice had more orexin neurons in the lateral hypothalamus. Blocking of orexin receptors differentially influenced heart rate in KO, but not wild-type (WT) mice. When DORA administration increased heart rate, it also decreased heart rate variability, breathing frequency, and/or hypopnea-apnea. Blocking orexin receptors prevented the methacholine (MCh)-induced increase in breathing frequency in KO mice and reduced MCh-induced seizures, via a direct or indirect mechanism. DORA improved oxygen saturation in KO mice with intermittent hypoxia. Daily administration of DORA to high-risk KO mice increased longevity. SIGNIFICANCE: High-risk KO mice have a unique cardiorespiratory phenotype that is characterized by progressive changes in five interdependent endpoints. Blocking of orexin receptors attenuates some of these endpoints and increases longevity, supporting the notion that windows of opportunity for intervention exist in this preclinical SUDEP model.


Assuntos
Apneia/genética , Bradicardia/genética , Epilepsia/genética , Hipóxia/genética , Canal de Potássio Kv1.1/genética , Morte Súbita Inesperada na Epilepsia , Animais , Apneia/fisiopatologia , Bradicardia/fisiopatologia , Epilepsia/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Região Hipotalâmica Lateral/metabolismo , Região Hipotalâmica Lateral/patologia , Hipóxia/fisiopatologia , Cloreto de Metacolina/toxicidade , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Neurônios/patologia , Antagonistas dos Receptores de Orexina/farmacologia , Orexinas/metabolismo , Oximetria , Oxigênio , Sistema Nervoso Parassimpático/fisiopatologia , Parassimpatomiméticos/toxicidade , Taxa Respiratória/efeitos dos fármacos , Convulsões/induzido quimicamente
10.
Clin Exp Hypertens ; 42(5): 409-419, 2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31589076

RESUMO

Background: Impaired orthostatic blood pressure (BP) response is a frequent finding in the elderly. The goal of the study was to investigate the association of variability of supine-to-orthostatic BP with cold pressor reflection and heart rate variability in the elderly.Methods: From June 2010 to September 2013, 287 elderly aged ≥ 60 years were enrolled in Jinan area, China. The elderly were classified into lower (n = 96), intermediate (n = 95), and higher (n = 96) tertile groups according to the tertile of the percentage change of supine-to-orthostatic systolic BP.Results: There were significant increasing trends in systolic BP response to the CPT at 0 and 60 sec; the plasma levels of epinephrine, norepinephrine, and angiotensin II; and decreasing trends in DNN, SDNN index, and SDANN from the lower to the higher tertile group, and differences between any two groups were significant (P < .05). The percentage change of supine-to-orthostatic systolic BP was positively correlated with systolic BP response to CPT at 0 and 60 sec, VLF, epinephrine, norepinephrine, and angiotensin II (P < .001) and negatively correlated with SDNN, SDNN index, SDANN, rMSSD, pNN50, LF, and ratio of LF/HF (P < .001). The BP response to CPT, parameters of HRV, and the plasma levels of norepinephrine and angiotensin II were independently associated with the percentage change of supine-to-orthostatic systolic BP after adjustment for confounders.Conclusion: Aggressive variability of supine-to-orthostatic systolic BP might be significantly associated with the imbalance of sympathetic and parasympathetic activity, especially high sensitivity sympathetic response in the elderly.Abbreviations: BP: blood pressure; BMI: body mass index; CPT: cold pressor test; HRV: heart rate variability; SDNN: standard deviation of all normal-to-normal R-R intervals; SDNN index: mean of the standard deviations of all 5-min normal-to-normal R-R intervals of the entire recording; SDANN: standard deviation of the averages of normal-to-normal R-R intervals during all 5-min periods of the entire recording; rMSSD: square root of the mean squared differences between successive normal R-R intervals; pNN50: number of adjacent normal R-R intervals differing by more than 50 ms; VLF: very low frequency; LF: low frequency; HF: high frequency; TCHO: total cholesterol; HDL-c: high-density lipoprotein cholesterol; LDL-c: low-density lipoprotein cholesterol; FPG: fasting plasma glucose; SD: standard deviation.


Assuntos
Envelhecimento/fisiologia , Resposta ao Choque Frio/fisiologia , Frequência Cardíaca/fisiologia , Hipotensão Ortostática , Sistema Nervoso Parassimpático/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Idoso , Pressão Sanguínea/fisiologia , China , Feminino , Humanos , Hipertensão/fisiopatologia , Hipotensão Ortostática/sangue , Hipotensão Ortostática/diagnóstico , Hipotensão Ortostática/etiologia , Hipotensão Ortostática/fisiopatologia , Masculino
13.
Int J Mol Sci ; 20(23)2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31783707

RESUMO

The present study aimed to investigate gene expression changes related to cell cycle activation in patients with spinal cord injury (SCI) and to further evaluate the difference between the upper and lower limbs of SCI patients. Fibroblasts were obtained from the upper and lower limbs of SCI patients and healthy subjects. To investigate gene expression profiling in the fibroblasts from SCI patients compared to the healthy subjects, RNA-Seq transcriptome analysis was performed. To validate the parasympathetic effects on cell cycle activation, fibroblasts from upper or lower limbs of SCI patients were treated with the anticholinergic agents tiotropium or acetylcholine, and quantitative RT-PCR and Western blot were conducted. Cell proliferation was significantly increased in the upper limbs of SCI patients compared with the lower limbs of SCI patients and healthy subjects. The pathway and genes involved in cell cycle were identified by RNA-Seq transcriptome analysis. Expression of cell-cycle-related genes CCNB1, CCNB2, PLK1, BUB1, and CDC20 were significantly higher in the upper limbs of SCI patients compared with the lower limbs of SCI patients and healthy subjects. When the fibroblasts were treated with tiotropium the upper limbs and acetylcholine in the lower limbs, the expression of cell-cycle-related genes and cell proliferation were significantly modulated. This study provided the insight that cell proliferation and cell cycle activation were observed to be significantly increased in the upper limbs of SCI patients via the parasympathetic effect.


Assuntos
Ciclo Celular/genética , Ciclo Celular/fisiologia , Sistema Nervoso Parassimpático/fisiopatologia , Traumatismos da Medula Espinal/fisiopatologia , Extremidade Superior/fisiologia , Adulto , Idoso , Proteínas de Ciclo Celular/genética , Proliferação de Células/genética , Fibroblastos/fisiologia , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/genética
14.
Braz J Cardiovasc Surg ; 34(5): 572-580, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31719008

RESUMO

OBJECTIVE: To characterize the behavior of cardiac autonomic modulation in individuals with different times after orthotopic heart transplantation (HTx) using symbolic dynamics analysis. METHODS: Sixty patients were evaluated after HTx. We recorded their instantaneous R-R intervals (RRi) by cardiac monitor Polar® RS800CX™ (Polar Electro Oy, Kempele, Finland) for 10 minutes. The same sequence of RRi with 256 consecutive beats was used to perform spectral analysis and symbolic dynamics analysis. We used hierarchical clustering to form groups. One-way analysis of variance (ANOVA) (with Holm-Sidak method) or one-way Kruskal-Wallis test (with Dunn´s post-hoc test) was used to analyze the difference between groups. Linear correlation analysis between variables was performed using Pearson's or Spearman's tests. P-value < 0.05 was considered statistically significant. RESULTS: The 0V% index increased, the 2UV% index and the normalized complexity index decreased with an increase of HTx postoperative time. There were a negative correlation between complexity indexes and 0V% and a positive correlation between complexity indexes and 2UV%. CONCLUSION: Symbolic dynamics indexes were able to show a specific cardiac autonomic modulation pattern for HTx recipients with different postoperative times.


Assuntos
Transplante de Coração/reabilitação , Coração/fisiopatologia , Dinâmica não Linear , Sistema Nervoso Parassimpático/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Adulto , Análise de Variância , Estudos Transversais , Entropia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Valores de Referência , Estudos Retrospectivos , Estatísticas não Paramétricas , Fatores de Tempo
15.
J Anxiety Disord ; 68: 102144, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31593854

RESUMO

BACKGROUND: Research on the link between respiratory sinus arrhythmia (RSA) and posttraumatic stress disorder (PTSD) has largely focused on average levels of RSA. However, given that rapid shifts in parasympathetic tone are necessary to maintain adaptive cardiac variability, the exclusive focus on these tonic estimates provides an incomplete quantification of parasympathetic cardiac regulation. METHOD: The present study is a secondary analysis of previously published data. This analysis aimed to address this limitation by examining the dynamic regulatory effect of the parasympathetic nervous system on heart rate. As such, we examined epoch-to-epoch parasympathetic cardiac regulation - operationalized as the lagged relationship between RSA and heart rate (HR) across consecutive 30-s epochs - across a single night in participants with PTSD, panic disorder (PD), comorbid PTSD and PD (PTSD + PD), and healthy controls. Electrocardiogram and respiratory signals were continuously recorded from 23 participants with PTSD, 14 with PD, 16 with PTSD + PD, and 16 control participants over a single night of sleep in a laboratory setting. RESULTS: No group differences in tonic RSA were observed; however, participants with PTSD only and PTSD + PD exhibited significantly greater epoch-to-epoch parasympathetic cardiac regulation over the night than those with PD only and control participants. Moreover, greater severity of hyperarousal symptoms was significantly associated with increased epoch-to-epoch parasympathetic cardiac regulation among participants with PTSD only and PTSD + PD. DISCUSSION: These data provide preliminary evidence for an upregulatory parasympathetic response to self-reported hyperarousal in participants with PTSD only and PTSD + PD reflected by increased epoch-to-epoch parasympathetic cardiac regulation.


Assuntos
Frequência Cardíaca , Transtorno de Pânico/fisiopatologia , Sistema Nervoso Parassimpático/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Estudos de Casos e Controles , Eletrocardiografia , Feminino , Humanos , Masculino , Autorrelato , Sono
16.
Drug Alcohol Depend ; 204: 107538, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31513980

RESUMO

BACKGROUND: Heart rate variability (HRV) is of interest to researchers due to its potential utility as a marker for both physiological and psychological stress. Sympatholytics are used to treat opioid withdrawal, but little information about the parasympathetic system's role in mediating withdrawal symptoms exists. The goal of the current study was to evaluate changes in HRV during opioid withdrawal to provide a better understanding of the autonomic effects of opioid withdrawal. METHODS: Ten male participants (mean age = 46.4 years) received intramuscular naloxone (mean dose =0.26 mg) to confirm opioid dependence. The presence and severity of withdrawal symptoms were assessed using subjective and objective measures (Wang et al., 1974). Electrocardiography (ECG) was measured continuously, and HRV was analyzed in 2-minute segments before naloxone injection (at baseline) and after participants were in moderate withdrawal (Wang Test score ≥10). Heart rate, blood pressure, pupil diameter, and respiratory rate were also examined. RESULTS: Pupil diameter significantly increased after naloxone administration relative to baseline (t(9) = 5.562, p = 0.000). Both high frequency (HF) HRV (Z = -2.803, p = 0.005) and root mean square of successive differences (RMSSD) HRV (Z = -2.090, p = 0.037) were significantly lower during withdrawal relative to baseline. Increases in heart rate (Z = -2.090, p = 0.032) and systolic pressure (t(9) = 8.099, p = 0.0000) from baseline to withdrawal also were significant. CONCLUSIONS: These preliminary data indicate that a large reduction in cardiac vagal tone occurs during naloxone-induced withdrawal. This finding underscores the need for further research into the role of the parasympathetic nervous system in opioid withdrawal.


Assuntos
Naloxona/uso terapêutico , Antagonistas de Entorpecentes/uso terapêutico , Transtornos Relacionados ao Uso de Opioides/fisiopatologia , Sistema Nervoso Parassimpático/efeitos dos fármacos , Síndrome de Abstinência a Substâncias/fisiopatologia , Adulto , Pressão Sanguínea/efeitos dos fármacos , Eletrocardiografia , Coração/efeitos dos fármacos , Coração/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Sistema Nervoso Parassimpático/fisiopatologia , Síndrome de Abstinência a Substâncias/tratamento farmacológico
17.
Eur J Clin Invest ; 49(11): e13174, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31560809

RESUMO

BACKGROUND: Atrial fibrillation (AF) is the commonest abnormal heart rhythm with significant related morbidity and mortality. Several pathophysiologic mechanisms have been advocated to explain the onset of AF. There has been increasing evidence that abnormalities of the autonomic nervous system (ANS) that includes sympathetic, parasympathetic and intrinsic neural network are involved in the pathogenesis of AF. This review will consider the anatomical and pathophysiological concepts of the cardiac neuronal network and discuss how it can be investigated. DESIGN: Relevant articles for this review were selected primarily from Ovid Medline and Embase databases (see appendix). We searched for key terms "atrial fibrillation," "AF," "autonomic dysfunction," "autonomic nervous system," "heart rate variability" and "HRV" to gather relevant studies. Duplicate papers were excluded. RESULTS: Heart is richly innervated by autonomic nerves. Both sympathetic and parasympathetic systems interact in developing AF along with cardiac ganglionated plexi (GP). Thus autonomic dysfunction is present in AF. There are methods including selective ablation that reduce autonomic innervation and show to reduce the incidence of spontaneous or induced atrial arrhythmias. Heart rate variability (HRV) is a useful tool to assess sympathetic and parasympathetic influences on disease states. HRV can be improved following intervention and is thus a useful application in assessing autonomic dysfunction in patients with AF. CONCLUSION: ANS plays a crucial role in the development, propagation and complexity of AF. Assessment of the autonomic involvement in the propagation of AF may help in explaining why certain patients with AF do not benefit from cardioversion or ablation.


Assuntos
Fibrilação Atrial/fisiopatologia , Frequência Cardíaca/fisiologia , Coração/inervação , Sistema Nervoso Parassimpático/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Humanos , Sistema Nervoso Parassimpático/fisiologia , Sistema Nervoso Simpático/fisiologia
18.
JCI Insight ; 4(20)2019 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-31503549

RESUMO

Atrial fibrillation (AF) is the most common heart rhythm disorder and a major cause of stroke. Unfortunately, current therapies for AF are suboptimal, largely because the molecular mechanisms underlying AF are poorly understood. Since the autonomic nervous system is thought to increase vulnerability to AF, we used a rapid atrial pacing (RAP) canine model to investigate the anatomic and electrophysiological characteristics of autonomic remodeling in different regions of the left atrium. RAP led to marked hypertrophy of parent nerve bundles in the posterior left atrium (PLA), resulting in a global increase in parasympathetic and sympathetic innervation throughout the left atrium. Parasympathetic fibers were more heterogeneously distributed in the PLA when compared with other left atrial regions; this led to greater fractionation and disorganization of AF electrograms in the PLA. Computational modeling revealed that heterogeneously distributed parasympathetic activity exacerbates sympathetic substrate for wave break and reentry. We further discovered that levels of nerve growth factor (NGF) were greatest in the left atrial appendage (LAA), where AF was most organized. Preferential NGF release by the LAA - likely a direct function of frequency and regularity of atrial stimulation - may have important implications for creation of a vulnerable AF substrate.


Assuntos
Apêndice Atrial/inervação , Fibrilação Atrial/fisiopatologia , Remodelamento Atrial , Fator de Crescimento Neural/metabolismo , Sistema Nervoso Parassimpático/fisiopatologia , Animais , Apêndice Atrial/citologia , Apêndice Atrial/patologia , Apêndice Atrial/fisiopatologia , Fibrilação Atrial/patologia , Modelos Animais de Doenças , Cães , Humanos , Miócitos Cardíacos/metabolismo
19.
Autism Res ; 12(12): 1805-1816, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31397547

RESUMO

Children with autism spectrum disorder (ASD) exhibit significant difficulties with emotion regulation and reactivity, which may be linked to underlying psychophysiology. The present study examined associations between autonomic nervous system activity and individual differences in externalizing behavior problems in children with ASD. A multisystem approach was adopted to consider the interplay between markers of sympathetic (electrodermal reactivity-EDA-R) and parasympathetic reactivity (respiratory sinus arrhythmia reactivity-RSA-R) in relation to behavioral challenges. Fifty-two children with ASD ages 6-10 years contributed complete psychophysiological data. Measures of EDA-R and RSA-R (RSA withdrawal) were obtained in response to a laboratory challenge task and parents reported on child externalizing behavior problems using a standardized questionnaire and a structured clinical interview. An equifinality model was supported, with two distinct psychophysiological pathways linked to heightened externalizing behavior problems. Greater RSA-R was associated with more externalizing problems in the context of higher levels of EDA-R, and lower EDA-R was associated with increased externalizing problems at lower levels of RSA-R. Findings underscore the importance of considering the role of psychophysiology in the unfolding of comorbid externalizing problems in children with ASD. Potential implications for tailoring coregulatory supports are discussed. Autism Res 2019, 12: 1805-1816. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Children with autism spectrum disorder (ASD) exhibit elevated rates of challenging behavior. This study identified specific psychophysiological profiles (low sympathetic-low parasympathetic reactivity, and high sympathetic-high parasympathetic reactivity) that may place these children at greater risk for behavior problems. Findings have implications for better understanding behavioral challenges in children with ASD, and for tailoring supports to address underlying psychophysiology.


Assuntos
Transtorno do Espectro Autista/complicações , Transtorno do Espectro Autista/fisiopatologia , Transtornos do Comportamento Infantil/complicações , Transtornos do Comportamento Infantil/fisiopatologia , Sistema Nervoso Parassimpático/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Transtorno do Espectro Autista/psicologia , Criança , Transtornos do Comportamento Infantil/psicologia , Feminino , Humanos , Individualidade , Masculino , Inquéritos e Questionários
20.
Medicina (Kaunas) ; 55(9)2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31454959

RESUMO

Background and objectives: In healthy individuals, autonomic alterations are associated with the aggregation of cardiovascular risk factors. However, in individuals with type 1 diabetes, who are known to present autonomic alterations, mainly characterized by a reduction in parasympathetic modulation, these associations have not yet been investigated. We assess whether the aggregation of cardiovascular risk factors influences parasympathetic indices of heart rate variability in young people with type 1 diabetes. Materials and methods: This cross-sectional study included 39 individuals with type 1 diabetes (22.54 ± 4.31), evaluated in relation to the risk factors: blood pressure, fat percentage, and resting heart rate. For heart rate variability analysis, heart rate was recorded beat-to-beat using a cardio frequency meter (PolarS810i) for 30 min with the volunteers in dorsal decubitus. The parasympathetic heart rate variability indices were calculated: rMSSD, pNN50, high frequency (HF) n.u (normalized units), SD1, 2LV, and 2ULV. Data collection was carried out in 2014 and analyzed in 2017. Results: Individuals with two aggregate risk factors present a reduction in the values of the indices that reflect parasympathetic autonomic modulation compared to individuals without the risk factors analyzed, regardless of sex and age. Conclusion: In young people with type 1 diabetes, the aggregation of cardiovascular risk factors is associated with parasympathetic autonomic impairment.


Assuntos
Doenças Cardiovasculares/complicações , Diabetes Mellitus Tipo 1/fisiopatologia , Frequência Cardíaca/fisiologia , Sistema Nervoso Parassimpático/fisiopatologia , Adolescente , Adulto , Pressão Sanguínea/fisiologia , Doenças Cardiovasculares/fisiopatologia , Estudos de Casos e Controles , Estudos Transversais , Diabetes Mellitus Tipo 1/complicações , Feminino , Humanos , Masculino , Sistema Nervoso Parassimpático/fisiologia , Fatores de Risco
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