Browsing by Author "Río Troncoso, Rodrigo Andre del"
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- ItemCardioventilatory Acclimatization Induced by Chronic Intermittent Hypoxia(2009) Iturriaga Agüera, Rodrigo; Rey Keim, Sergio; Río Troncoso, Rodrigo Andre del; Moya Céspedes, Esteban Alexis.
- ItemCarotid body and cardiorespiratory alterations in intermittent hypoxia: the oxidative link(2010) Río Troncoso, Rodrigo Andre del; Moya Céspedes, Esteban Alexis.; Iturriaga Agüera, Rodrigo
- ItemCarotid body chemoreceptors, sympathetic neural activation, and cardiometabolic disease(2016) Iturriaga Agüera, Rodrigo; Río Troncoso, Rodrigo Andre del; Idiaquez, Juan.; Somers, Virend K.Abstract The carotid body (CB) is the main peripheral chemoreceptor that senses the arterial PO2, PCO2 and pH. In response to hypoxemia, hypercapnia and acidosis, carotid chemosensory discharge elicits reflex respiratory, autonomic and cardiovascular adjustments. The classical construct considers the CB as the main peripheral oxygen sensor, triggering reflex physiological responses to acute hypoxemia and facilitating the ventilatory acclimation to chronic hypoxemia at high altitude. However, a growing body of experimental evidence supports the novel concept that an abnormally enhanced CB chemosensory input to the brainstem contributes to overactivation of the sympathetic nervous system, and consequent pathology. Indeed, the CB has been implicated in several diseases associated with increases in central sympathetic outflow. These include hypertension, heart failure, sleep apnea, chronic obstructive pulmonary disease and metabolic syndrome. Indeed, ablation of the CB has been proposed for the treatment of severe and resistant hypertension in humans. In this review, we will analyze and discuss new evidence supporting an important role for the CB chemoreceptor in the progression of autonomic and cardiorespiratory alterations induced by heart failure, obstructive sleep apnea, chronic obstructive pulmonary disease and metabolic syndrome.Abstract The carotid body (CB) is the main peripheral chemoreceptor that senses the arterial PO2, PCO2 and pH. In response to hypoxemia, hypercapnia and acidosis, carotid chemosensory discharge elicits reflex respiratory, autonomic and cardiovascular adjustments. The classical construct considers the CB as the main peripheral oxygen sensor, triggering reflex physiological responses to acute hypoxemia and facilitating the ventilatory acclimation to chronic hypoxemia at high altitude. However, a growing body of experimental evidence supports the novel concept that an abnormally enhanced CB chemosensory input to the brainstem contributes to overactivation of the sympathetic nervous system, and consequent pathology. Indeed, the CB has been implicated in several diseases associated with increases in central sympathetic outflow. These include hypertension, heart failure, sleep apnea, chronic obstructive pulmonary disease and metabolic syndrome. Indeed, ablation of the CB has been proposed for the treatment of severe and resistant hypertension in humans. In this review, we will analyze and discuss new evidence supporting an important role for the CB chemoreceptor in the progression of autonomic and cardiorespiratory alterations induced by heart failure, obstructive sleep apnea, chronic obstructive pulmonary disease and metabolic syndrome.
- ItemCarotid body potentiation during chronic intermittent hypoxia: implication for hypertension(2014) Río Troncoso, Rodrigo Andre del; Moya Céspedes, Esteban Alexis.; Iturriaga Agüera, Rodrigo
- ItemCarotid body potentiation induced by intermittent hypoxia: Implications for cardiorespiratory changes induced by sleep apnoea(2009) Iturriaga Agüera, Rodrigo; Moya Céspedes, Esteban Alexis.; Río Troncoso, Rodrigo Andre del
- ItemChemogenetic inhibition of NTS astrocytes normalizes cardiac autonomic control and ameliorate hypertension during chronic intermittent hypoxia(2023) Pereyra Florián, Katherin Vanessa; Las Heras, Alexandra; Toledo, Camilo; Díaz-Jara, Esteban; Iturriaga, Rodrigo; Río Troncoso, Rodrigo Andre delAbstract Background Obstructive sleep apnea (OSA) is characterized by recurrent episodes of chronic intermittent hypoxia (CIH), which has been linked to the development of sympathoexcitation and hypertension. Furthermore, it has been shown that CIH induced inflammation and neuronal hyperactivation in the nucleus of the solitary tract (NTS), a key brainstem region involved in sympathetic and cardiovascular regulation. Since several studies have proposed that NTS astrocytes may mediate neuroinflammation, we aimed to determine the potential contribution of NTS-astrocytes on the pathogenesis of CIH-induced hypertension. Results Twenty-one days of CIH induced autonomic imbalance and hypertension in rats. Notably, acute chemogenetic inhibition (CNO) of medullary NTS astrocytes using Designer Receptors Exclusively Activated by Designers Drugs (DREADD) restored normal cardiac variability (LF/HF: 1.1 ± 0.2 vs. 2.4 ± 0.2 vs. 1.4 ± 0.3, Sham vs. CIH vs. CIH + CNO, respectively) and markedly reduced arterial blood pressure in rats exposed to CIH (MABP: 82.7 ± 1.2 vs. 104.8 ± 4.4 vs. 89.6 ± 0.9 mmHg, Sham vs. CIH vs. CIH + CNO, respectively). In addition, the potentiated sympathoexcitation elicit by acute hypoxic chemoreflex activation in rats exposed to CIH was also completely abolished by chemogenetic inhibition of NTS astrocytes using DREADDs. Conclusion Our results support a role for NTS astrocytes in the maintenance of heightened sympathetic drive and hypertension during chronic exposure to intermittent hypoxia mimicking OSA.
- ItemComparative respiratory strategies of subterranean and fossorial octodontid rodents to cope with hypoxic and hypercapnic atmospheres(2010) Tomasco, I. H.; Río Troncoso, Rodrigo Andre del; Iturriaga Agüera, Rodrigo; Bozinovic Kuscevic, Francisco
- ItemContribution of inflammation on carotid body chemosensory potentiation induced by intermittent hypoxia(2012) Río Troncoso, Rodrigo Andre del; Moya Céspedes, Esteban Alexis.; Iturriaga Agüera, Rodrigo
- ItemContribution of TASK-like potassium channels to the enhanced rat carotid body responsiveness to hypoxia.(2012) Ortiz Cisternas, Fernando Andrés.; Río Troncoso, Rodrigo Andre del; Varas Orozco, Rodrigo; Iturriaga Agüera, Rodrigo
- ItemDietary supplementation of a sulforaphane-enriched broccoli extract protects the heart from acute cardiac stress(2020) Pereyra Florián, Katherin Vanessa; Andrade Andrade, David Cristóbal; Toledo, C.; Schwarz Flores, Karla Gabriele; Uribe-Ojeda, A.; Ríos-Gallardo, A. P.; Quintanilla, Rodrigo A.; Contreras E., Samuel; Mahn, A.; Río Troncoso, Rodrigo Andre del
- ItemDifferential expression of pro-inflammatory cytokines, endothelin-1 and nitric oxide synthases in the rat carotid body exposed to intermittent hypoxia(2011) Río Troncoso, Rodrigo Andre del; Moya Céspedes, Esteban Alexis.; Iturriaga Agüera, Rodrigo
- ItemEffects of enriched-potassium diet on cardiorespiratory outcomes in experimental non-ischemic chronic heart failure(2021) Schwarz Flores, Karla Gabriele; Pereyra Florián, Katherin Vanessa; Toledo, Camilo; Andrade Andrade, David Cristóbal; Díaz, Hugo S.; Díaz Jara, Esteban; Ortiz Cisternas, Fernando Andrés; Inestrosa Cantín, Nibaldo; Vio Lagos, Carlos P.; Río Troncoso, Rodrigo Andre delChronic heart failure (CHF) is a global health problem. Increased sympathetic outfow, cardiac arrhythmogenesis and irregular breathing patterns have all been associated with poor outcomes in CHF. Several studies showed that activation of the renin-angiotensin system (RAS) play a key role in CHF pathophysiology. Interestingly, potassium (K+) supplemented diets showed promising results in normalizing RAS axis and autonomic dysfunction in vascular diseases, lowering cardiovascular risk. Whether subtle increases in dietary K+ consumption may exert similar efects in CHF has not been previously tested. Accordingly, we aimed to evaluate the efects of dietary K+ supplementation on cardiorespiratory alterations in rats with CHF. Methods: Adult male Sprague–Dawley rats underwent volume overload to induce non-ischemic CHF. Animals were randomly allocated to normal chow diet (CHF group) or supplemented K+ diet (CHF+K+ group) for 6 weeks. Cardiac arrhythmogenesis, sympathetic outfow, barorefex sensitivity, breathing disorders, chemorefex function, respiratory–cardiovascular coupling and cardiac function were evaluated. Results: Compared to normal chow diet, K+ supplemented diet in CHF signifcantly reduced arrhythmia incidence (67.8±15.1 vs. 31.0±3.7 events/hour, CHF vs. CHF+K+), decreased cardiac sympathetic tone (ΔHR to propranolol: −97.4±9.4 vs. −60.8±8.3 bpm, CHF vs. CHF+K+), restored barorefex function and attenuated irregular breathing patterns. Additionally, supplementation of the diet with K+ restores normal central respiratory chemorefex drive and abrogates pathological cardio-respiratory coupling in CHF rats being the outcome an improved cardiac function. Conclusion: Our fndings support that dietary K+ supplementation in non-ischemic CHF alleviate cardiorespiratory dysfunction.
- ItemEffects of vagotomy on cardiovascular and heart rate variability alterations following chronic normobaric hypoxia in adult rabbits(2018) Alcayaga Urbina, Julio Andrés; Río Troncoso, Rodrigo Andre del; Moya Céspedes, Esteban Alexis.; Freire, Matías.; Iturriaga Agüera, RodrigoAbstract Background chronic hypoxia increases basal ventilation and pulmonary vascular resistance, with variable changes in arterial blood pressure and heart rate, but it’s impact on heart rate variability and autonomic regulation have been less well examined. We studied changes in arterial blood pressure, heart rate and heart rate variability (HRV) in rabbits subjected to chronic normobaric hypoxia (CNH; PB ~ 719 mmHg; FIO2 ~ 9.2%) for 14 days and assess the effect of autonomic control by acute bilateral vagal denervation. Results exposure to CNH stalled animal weight gain and increased the hematocrit, without affecting heart rate or arterial blood pressure. Nevertheless, Poincaré plots of the electrocardiographic R–R intervals showed a reduced distribution parallel to the line of identity, which interpreted as reduced long-term HRV. In the frequency domain, CNH reduced the very-low- (< 0.2 Hz) and high-frequency components (> 0.8 Hz) of the R–R spectrograms and produced a prominent component in the low-frequency component (0.2–0.5 Hz) of the power spectrum. In control and CNH exposed rabbits, bilateral vagotomy had no apparent effect on the short- and long-term HRV in the Poincaré plots. However, bilateral vagotomy differentially affected higher-frequency components (> 0.8 Hz); reducing it in control animals without modifying it in CNH-exposed rabbits. Conclusions These results suggest that CNH exposure shifts the autonomic balance of heart rate towards a sympathetic predominance without modifying resting heart rate or arterial blood pressure.
- ItemEvidence for Histamine as a New Modulator of Carotid Body Chemoreception(2009) Río Troncoso, Rodrigo Andre del; Moya Céspedes, Esteban Alexis.; Iturriaga Agüera, Rodrigo
- ItemHeart rate and cardiac autonomic responses to concomitant deep breathing, hand grip exercise, and circulatory occlusion in healthy young adult men and women(2021) Andrade Andrade, David Cristóbal; Melipillan, Claudia; Toledo, Camilo; Rios-Gallardo, Angélica; Marcus, Noah J.; Ortiz, Fernando C.; Martinez, Gonzalo; Muñoz Venturelli, Paula; Río Troncoso, Rodrigo Andre delBackground: Deep breathing (DB) and handgrip (HG) exercise -with and without circulatory occlusion (OC) in muscle-, have been shown to have beneficial effects on cardiovascular function; however, the combination of these maneuvers on heart rate (HR) and cardiac sympathovagal balance have not been previously investigated. Therefore, the aim of the present study was to evaluate the effect of simultaneous DB, HG, and OC maneuvers on the sympathovagal balance in healthy women and men subjects. Methods and results: Electrocardiogram and ventilation were measured in 20 healthy subjects (Women: n = 10; age = 27 ± 4 years; weight = 67.1 ± 8.4 kg; and height = 1.6 ± 0.1 m. Men: n = 10; age = 27 ± 3 years; weight = 77.5 ± 10.1 kg; and height = 1.7 ± 0.1 m) at baseline and during DB, DB + HG, or DB + HG + OC protocols. Heart rate (HR) and respiratory rate were continuously recorded, and spectral analysis of heart rate variability (HRV) were calculated to indirectly estimate cardiac autonomic function. Men and women showed similar HR responses to DB, DB + HG and DB + HG + OC. Men exhibited a significant HR decrease following DB + HG + OC protocol which was accompanied by an improvement in cardiac autonomic control evidenced by spectral changes in HRV towards parasympathetic predominance (HRV High frequency: 83.95 ± 1.45 vs. 81.87 ± 1.50 n.u., DB + HG + OC vs. baseline; p < 0.05). In women, there was a marked decrease in HR after completion of both DB + HG and DB + HG + OC tests which was accompanied by a significant increase in cardiac vagal tone (HRV High frequency: 85.29 ± 1.19 vs. 77.93 ± 0.92 n.u., DB + HG vs. baseline; p < 0.05). No adverse effects or discomfort were reported by men or women during experimental procedures. Independent of sex, combination of DB, HG, and OC was tolerable and resulted in decreases in resting HR and elevations in cardiac parasympathetic tone. Conclusions: These data indicate that combined DB, HG and OC are effective in altering cardiac sympathovagal balance and reducing resting HR in healthy men and women.
- ItemInflammation and oxidative stress during intermittent hypoxia: the impact on chemoreception(2015) Iturriaga Agüera, Rodrigo; Moya Céspedes, Esteban Alexis.; Río Troncoso, Rodrigo Andre del
- ItemInhibition of rat carotid body glomus cells TASK-like channels by acute hypoxia is enhanced by chronic intermittent hypoxia(2013) Ortiz Cisternas, Fernando Andrés.; Río Troncoso, Rodrigo Andre del; Varas Orozco, Rodrigo; Iturriaga Agüera, Rodrigo
- ItemIntranasal oxytocin increases respiratory rate and reduces obstructive event duration and oxygen desaturation in obstructive sleep apnea patients : a randomized double blinded placebo controlled study(2020) Jain, V.; Kimbro, S.; Kowalik, G.; Milojevic, I.; Dowling, N. Maritza; Hunley, A. L.; Hauser, K.; Andrade Andrade, David Cristóbal; Río Troncoso, Rodrigo Andre del; Kay, M. W.; Mendelowitz D.
- ItemModulatory effects of histamine on cat carotid body chemoreception(2008) Río Troncoso, Rodrigo Andre del; Moya Céspedes, Esteban Alexis.; Iturriaga Agüera, Rodrigo
- ItemPotential Role of Autonomic Dysfunction in Covid-19 Morbidity and Mortality(2020) Río Troncoso, Rodrigo Andre del; Marcus, N. J.; Inestrosa Cantín, Nibaldo