|2015||Baumert M, Pamula Y, Kohler M, Martin J, Kennedy D, Nalivaiko E, Immanuel SA, 'Effect of respiration on heartbeat-evoked potentials during sleep in children with sleep-disordered breathing', Sleep Medicine, (2015)|
Objective: Heartbeat-evoked potentials (HEPs) in electroencephalogram (EEG) provide a quantitative measure of cardiac interoception during sleep. We previously reported reduced HEPs in children with sleep-disordered breathing (SDB), indicative of attenuated cardiac information processing. The objective of this study was to investigate the link between HEP and respiration. Patients/Methods: From the overnight polysomnograms of 40 healthy children and 40 children with SDB, we measured HEPs during epochs of stage 2, slow-wave and rapid eye movement (REM) sleep free of abnormal respiratory events. HEPs were analysed with respect to respiratory phase. Results: We observed a marked association between respiratory phase and HEP in children with SDB during REM sleep, but not in normal children. In children with SDB, HEP waveforms were attenuated during expiration compared to inspiration. Following adenotonsillectomy, expiratory HEP peak amplitude increased in the SDB children and was no longer different from those of normal children. Conclusions: The expiratory phase of respiration is primarily associated with attenuated cardiac information processing in children with SDB, establishing a pathophysiological link between breathing and HEP attenuation.
|2015||Bondarenko E, Beig MI, Hodgson DM, Braga VA, Nalivaiko E, 'Blockade of the dorsomedial hypothalamus and the perifornical area inhibits respiratory responses to arousing and stressful stimuli.', Am J Physiol Regul Integr Comp Physiol, 308 R816-R822 (2015)|
|2015||Silva NT, Nalivaiko E, da Silva LG, Haibara AS, 'Excitatory amino acid receptors in the dorsomedial hypothalamic area contribute to the chemoreflex tachypneic response.', Respir Physiol Neurobiol, 212-214 1-8 (2015)|
|2014||Ngampramuan S, Cerri M, del Vecchio F, Corrigan JJ, Kamphee A, Dragic AS, et al., 'Thermoregulatory correlates of nausea in rats and musk shrews', Oncotarget, 5 1565-1575 (2014) [C1]|
Nausea is a prominent symptom and major cause of complaint for patients receiving anticancer chemo- or radiation therapy. The arsenal of anti-nausea drugs is limited, and their efficacy is questionable. Currently, the development of new compounds with anti-nausea activity is hampered by the lack of physiological correlates of nausea. Physiological correlates are needed because common laboratory rodents lack the vomiting reflex. Furthermore, nausea does not always lead to vomiting. Here, we report the results of studies conducted in four research centers to investigate whether nausea is associated with any specific thermoregulatory symptoms. Two species were studied: the laboratory rat, which has no vomiting reflex, and the house musk shrew (Suncus murinus), which does have a vomiting reflex. In rats, motion sickness was induced by rotating them in their individual cages in the horizontal plane (0.75 Hz, 40 min) and confirmed by reduced food consumption at the onset of dark (active) phase. In 100% of rats tested at three centers, postrotational sickness was associated with marked (~1.5Â°C) hypothermia, which was associated with a short-lasting tail-skin vasodilation (skin temperature increased by ~4Â°C). Pretreatment with ondansetron, a serotonin 5-HT3 receptor antagonist, which is used to treat nausea in patients in chemo- or radiation therapy, attenuated hypothermia by ~30%. In shrews, motion sickness was induced by a cyclical backand-forth motion (4 cm, 1 Hz, 15 min) and confirmed by the presence of retching and vomiting. In this model, sickness was also accompanied by marked hypothermia (~2Â°C). Like in rats, the hypothermic response was preceded by transient tail-skin vasodilation. In conclusion, motion sickness is accompanied by hypothermia that involves both autonomic and thermoeffector mechanisms: tail-skin vasodilation and possibly reduction of the interscapular brown adipose tissue activity. These thermoregulatory symptoms may serve as physiological correlates of nausea.
|2014||Xavier CH, Ianzer D, Lima AM, Marins FR, Pedrino GR, Vaz G, et al., 'Excitatory amino acid receptors mediate asymmetry and lateralization in the descending cardiovascular pathways from the dorsomedial hypothalamus', PLoS ONE, 9 (2014) [C1]|
The dorsomedial hypothalamus (DMH) and lateral/dorsolateral periaqueductal gray (PAG) are anatomically and functionally connected. Both the DMH and PAG depend on glutamatergic inputs for activation. We recently reported that removal of GABA-ergic tone in the unilateral DMH produces: asymmetry, that is, a right- (R-) sided predominance in cardiac chronotropism, and lateralization, that is, a greater increase in ipsilateral renal sympathetic activity (RSNA). In the current study, we investigated whether excitatory amino acid (EAA) receptors in the DMH-PAG pathway contribute to the functional interhemispheric difference. In urethane (1.2 to 1.4 g/kg, i.p.) anesthetized rats, we observed that: (i) nanoinjections of N-methyl D-aspartate (NMDA 100 pmol/100 nl) into the unilateral DMH produced the same right-sided predominance in the control of cardiac chronotropy, (ii) nanoinjections of NMDA into the ipsilateral DMH or PAG evoked lateralized RSNA responses, and (iii) blockade of EAA receptors in the unilateral DMH attenuated the cardiovascular responses evoked by injection of NMDA into either the R- or left- (L-) PAG. In awake rats, nanoinjection of kynurenic acid (1 nmol/100 nL) into the L-DMH or R- or L-PAG attenuated the tachycardia evoked by air stress. However, the magnitude of stress-evoked tachycardia was smallest when the EAA receptors of the R-DMH were blocked. We conclude that EAA receptors contribute to the right-sided predominance in cardiac chronotropism. This interhemispheric difference that involves EAA receptors was observed in the DMH but not in the PAG.
|2014||Fontes MAP, Xavier CH, Marins FR, LimborÃ§o-Filho M, Vaz GC, MÃ¼ller-Ribeiro FC, Nalivaiko E, 'Emotional stress and sympathetic activity: Contribution of dorsomedial hypothalamus to cardiac arrhythmias', Brain Research, 1554 49-58 (2014) [C1]|
Maintenance of homeostasis in normal or stressful situations depends upon mechanisms controlling autonomic activity. Central requirement for changes in sympathetic output resulting from emotional stress must be adjusted to the input signals from visceral sensory afferent (feedback response) for an optimum cardiovascular performance. There is a large body of evidence indicating that emotional stress can lead to cardiovascular disease. Reviewing the descending pathways from dorsomedial hypothalamus, a key region involved in the cardiovascular response to emotional stress, we discuss the interactions between mechanisms controlling the sympathetic output to the cardiovascular system and the possible implications in cardiovascular disease. Â© 2014 Elsevier B.V.
|2014||Del Vecchio F, Nalivaiko E, Cerri M, Luppi M, Amici R, 'Provocative motion causes fall in brain temperature and affects sleep in rats', Experimental Brain Research, 232 2591-2599 (2014) [C1]|
Neural substrate of nausea is poorly understood, contrasting the wealth of knowledge about the emetic reflex. One of the reasons for this knowledge deficit is limited number and face validity of animal models of nausea. Our aim was to search for new physiological correlates of nausea in rats. Specifically, we addressed the question whether provocative motion (40-min rotation at 0.5 Hz) affects sleep architecture, brain temperature, heart rate (HR) and arterial pressure. Six adult male Sprague-Dawley rats were instrumented for recordings of EEG, nuchal electromyographic, hypothalamic temperature and arterial pressure. Provocative motion had the following effects: (1) total abolition of REM sleep during rotation and its substantial reduction during the first hour post-rotation (from 20 Â± 3 to 5 Â± 1.5 %); (2) reduction in NREM sleep, both during rotation (from 57 Â± 6 to 19 Â± 5 %) and during the first hour post-rotation (from 56 Â± 3 to 41 Â± 9 %); (3) fall in the brain temperature (from 37.1 Â± 0.1 to 36.0 Â± 0.1Â°C); and (4) reduction in HR (from 375 Â± 6 to 327 Â± 7 bpm); arterial pressure was not affected. Ondansetron, a 5-HT3 antagonist, had no major effect on all observed parameters during both baseline and provocative motion. We conclude that in rats, provocative motion causes prolonged arousing effects, however without evidence of sympathetic activation that usually accompanies heightened arousal. Motion-induced fall in the brain temperature complements and extends our previous observations in rats and suggests that similar to humans, provocative motion triggers coordinated thermoregulatory response, leading to hypothermia in this species. Â© 2014 Springer-Verlag.
|2014||Carnevali L, Trombini M, Graiani G, Madeddu D, Quaini F, Landgraf R, et al., 'Low vagally-mediated heart rate variability and to ventricular arrhythmias in rats bred for high increased susceptibility anxiety', PHYSIOLOGY & BEHAVIOR, 128 16-25 (2014) [C1]|
|2014||Immanuel SA, Pamula Y, Kohler M, Martin J, Kennedy D, Nalivaiko E, et al., 'Heartbeat Evoked Potentials during Sleep and Daytime Behavior in Children with Sleep-disordered Breathing', AMERICAN JOURNAL OF RESPIRATORY AND CRITICAL CARE MEDICINE, 190 1149-1157 (2014) [C1]|
|2014||Queiroz TM, Mendes-JÃºnior LG, GuimarÃ£es DD, FranÃ§a-Silva MS, Nalivaiko E, Braga VA, 'Corrigendum to "Cardiorespiratory effects induced by 2-nitrate-1,3-dibuthoxypropan are reduced by nitric oxide scavenger in rats." [Auton. Neurosci. 181 (April 2014) 31-36]', Autonomic Neuroscience: Basic and Clinical, 185 152-152 (2014) [O1]|
|2014||Queiroz TM, Mendes-JÃºnior LG, GuimarÃ£es DD, FranÃ§a-Silva MS, Nalivaiko E, Braga VA, 'Cardiorespiratory effects induced by 2-nitrate-1,3-dibuthoxypropan are reduced by nitric oxide scavenger in rats', Autonomic Neuroscience: Basic and Clinical, 181 31-36 (2014) [C1]|
|2014||Bondarenko E, Hodgson DM, Nalivaiko E, 'Prelimbic prefrontal cortex mediates respiratory responses to mild and potent prolonged, but not brief, stressors', RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY, 204 21-27 (2014) [C1]|
|2014||Carnevali L, Nalivaiko E, Sgoifo A, 'Respiratory patterns reflect different levels of aggressiveness and emotionality in Wild-type Groningen rats', Respiratory Physiology and Neurobiology, 204 28-35 (2014) [C1]|
Respiratory patterns represent a promising physiological index for assessing emotional states in preclinical studies. Since disturbed emotional regulation may lead to forms of excessive aggressiveness, in this study we investigated the hypothesis that rats that differ largely in their level of aggressive behavior display matching alterations in respiration. Respiration was recorded in male high-aggressive (HA, n=. 8) and non-aggressive (NA, n=. 8) Wild-type Groningen rats using whole-body plethysmography. Subsequently, anxiety-related behaviors were evaluated in the elevated plus maze and social avoidance-approach tests. During respiratory testing, HA rats showed elevated basal respiratory rate, reduced sniffing, exaggerated tachypnoeic response to an acoustic stimulus and a larger incidence of sighs. In addition, HA rats spent less time in the open arms of the plus maze and displayed higher levels of social avoidance behavior compared to NA rats. These findings indicate that HA rats are characterized by alterations in respiratory functioning and behavior that are overall indicative of an anxiety-like phenotype.
|2014||Bondarenko E, Hodgson DM, Nalivaiko E, 'Prelimbic prefrontal cortex mediates respiratory responses to mild and potent prolonged, but not brief, stressors', Respiratory Physiology and Neurobiology, 204 21-27 (2014) [C1]|
The prefrontal cortex is one of the key areas of the central mechanism of cardiovascular and respiratory control. Disinhibition of the prelimbic medial prefrontal cortex elicits tachypnoeic responses in anesthetized rats (Hassan et al., J. Physiol. 591: 6069-6088, 2013). The current study examines the effects of inhibition of the prelimbic prefrontal cortex during presentation of stressors of various lengths and intensities in conscious unrestrained rats. 8 Wistar rats were implanted with bilateral guide cannulas targeting the prelimbic prefrontal cortex and received microinjections of either saline of GABAA agonist muscimol prior to recording sessions. Inhibition of the prelimbic prefrontal cortex significantly attenuated respiratory responses to a novel environment stress, 30s light stimulus and restraint stress. It did not affect respiratory responses to 500ms acoustic stimuli of varying intensities (40-90dB). We conclude that the prelimbic prefrontal cortex contributes to generation of tachypnoeic responses to prolonged stressors, but does not contribute to respiratory arousal in response to brief stressors.
|2014||Davenport P, Nalivaiko E, 'Introduction to Special Issue "Non-homeostatic Control of Respiration"', Respiratory Physiology and Neurobiology, 204 1-2 (2014) [C3]|
|2014||Bondarenko E, Hodgson DM, Nalivaiko E, 'Amygdala mediates respiratory responses to sudden arousing stimuli and to restraint stress in rats.', Am J Physiol Regul Integr Comp Physiol, 306 R951-R959 (2014) [C1]|
|2013||Carnevali L, Trombini M, Rossi S, Graiani G, Manghi M, Koolhaas JM, et al., 'Structural and Electrical Myocardial Remodeling in a Rodent Model of Depression', PSYCHOSOMATIC MEDICINE, 75 42-51 (2013) [C1]|
|2013||Ngampramuan S, Baumert M, Czippelova B, Nalivaiko E, 'Ondansetron prevents changes in respiratory pattern provoked by LiCl: A new approach for studying pro-emetic states in rodents?', Neuroscience, 246 342-350 (2013) [C1]|
There are a limited number of biological indices for assessing pro-emetic states in laboratory rodents as they do not possess the vomiting response. In the present study we tested the hypothesis that in rats, pro-emetic intervention would affect the respiratory pattern. To this end, using whole-body plethysmography, in adult male Wistar rats we recorded respiration after i.p. administration of either the emetic agent LiCl or Ringer. Quantification of respiratory signals (from 5 to 35min post-injection) revealed that post-LiCl, mean respiratory rate was significantly lower (126Â±9 vs. 178Â±10cpm, p<0.005) and less variable (Kvar 59Â±8% vs. 73Â±3%; p<0.05) compared to the post-Ringer condition. Furthermore, while mode values of respiratory rate histograms did not differ between the treatments (indicating that the dominant respiratory frequency remained unchanged), LiCl reduced the fraction of time spent at high respiratory rate (>200cpm) from 25Â±3% to 9Â±2% (p=0.004). Thus, reduction of the mean respiratory rate by LiCl was predominantly due to reduced contribution of high-frequency breathing that is normally associated with motor activity and/or arousal. Non-linear multifractal analysis of respiratory signals revealed that post-LiCl, respiration becomes less random and more orderly. 5-HT3 antagonist ondansetron prevented respiratory changes elicited by LiCl. We conclude that the observed changes likely reflect effects of LiCl on animals' motion, and that this effect is mediated via 5-HT3 receptors. Providing that the effects observed in our study were quite robust, we suggest that simple and non-invasive respiratory monitoring may be a promising approach for studying emesis in rodents. Â© 2013 IBRO.
|2013||Xavier CH, Beig MI, Ianzer D, Peliky Fontes MA, Nalivaiko E, 'Asymmetry in the control of cardiac performance by dorsomedial hypothalamus', AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY INTEGRATIVE AND COMPARATIVE PHYSIOLOGY, 304 R664-R674 (2013) [C1]|
|2013||Bobrovskaya L, Beard D, Bondarenko E, Beig MI, Jobling P, Walker FR, et al., 'Does exposure to chronic stress influence blood pressure in rats?', AUTONOMIC NEUROSCIENCE-BASIC & CLINICAL, 177 217-223 (2013) [C1]|
|2013||Sominsky L, Fuller EA, Bondarenko E, Ong LK, Averell L, Nalivaiko E, et al., 'Functional Programming of the Autonomic Nervous System by Early Life Immune Exposure: Implications for Anxiety', PLOS ONE, 8 (2013) [C1]|
|2013||Carnevali L, Sgoifo A, Trombini M, Landgraf R, Neumann ID, Nalivaiko E, 'Different Patterns of Respiration in Rat Lines Selectively Bred for High or Low Anxiety', PLOS ONE, 8 (2013) [C1]|
|2012||Iigaya K, Muller-Ribeiro FCDF, Horiuchi J, McDowall LM, Nalivaiko E, Fontes MAP, Dampney RAL, 'Synchronized activation of sympathetic vasomotor, cardiac, and respiratory outputs by neurons in the midbrain colliculi', American Journal of Physiology - Regulatory Integrative and Comparative Physiology, 303 R599-R610 (2012) [C1]|
|2012||Nalivaiko E, Bondarenko E, Lidstrom A, Barry RJ, 'Respiratory component of the orienting reflex: A novel sensitive index of sensory-induced arousal in rats', Frontiers in Physiology, 2 1-6 (2012) [C1]|
|2012||Carnevali L, Mastorci F, Audero E, Graiani G, Rossi S, Macchi E, et al., 'Stress-induced susceptibility to sudden cardiac death in mice with altered serotonin homeostasis', PLoS One, 7 e41184 (2012) [C1]|
|2011||Kabir MM, Saint DA, Nalivaiko E, Abbott D, Voss A, Baumert M, 'Quantification of cardiorespiratory interactions based on joint symbolic dynamics', Annals of Biomedical Engineering, 39 2604-2614 (2011) [C1]|| |
|2011||Kabir MM, Saint DA, Nalivaiko E, Abbott D, Baumert M, 'Time delay correction of the synchrogram for optimized detection of cardiorespiratory coordination', Medical and Biological Engineering and Computing, 49 1249-1259 (2011) [C1]|| |
|2011||Beig MI, Callister R, Saint DA, Bondarenko E, Walker FR, Day TA, Nalivaiko E, 'Voluntary exercise does not affect stress-induced tachycardia, but improves resistance to cardiac arrhythmias in rats', Clinical and Experimental Pharmacology and Physiology, 38 19-26 (2011) [C1]|| |
|2011||Nalivaiko E, 'Animal models of psychogenic cardiovascular disorders: What we can learn from them and what we cannot', Clinical and Experimental Pharmacology and Physiology, 38 115-125 (2011) [C1]|
|2011||Carnevali L, Bondarenko E, Sgoifo A, Walker FR, Head GA, Lukoshkova EV, et al., 'Metyrapone and fluoxetine suppress enduring behavioral but not cardiac effects of subchronic stress in rats', American Journal of Physiology-Regulatory Integrative and Comparative Physiology, 301 R1123-R1131 (2011) [C1]|| |
|2011||Baumert M, Schlaich MP, Nalivaiko E, Lambert E, Sari CI, Kaye DM, et al., 'Relation between QT interval variability and cardiac sympathetic activity in hypertension', American Journal of Physiology - Heart and Circulatory Physiology, 300 H1412-H1417 (2011) [C1]|| |
|2011||Baumert M, Lambert E, Vaddadi G, Sari CI, Esler M, Lambert G, et al., 'Cardiac repolarization variability in patients with postural tachycardia syndrome during graded head-up tilt', Clinical Neurophysiology, 122 405-409 (2011) [C1]|| |
|2010||Kabir MM, Dimitri H, Sanders P, Antic R, Nalivaiko E, Abbott D, Baumert M, 'Cardiorespiratory phase-coupling is reduced in patients with obstructive sleep apnea', Plos One, 5 1-12 (2010) [C1]|| |
|2010||Kabir MM, Beig MI, Baumert M, Trombini M, Mastorci F, Sgoifo A, et al., 'Respiratory pattern in awake rats: Effects of motor activity and of alerting stimuli', Physiology and Behavior, 101 22-31 (2010) [C1]|| |
|2010||Mackenzie LJ, Nalivaiko E, Beig MI, Day TA, Walker FR, 'Ability of predator odour exposure to elicit conditioned versus sensitised post traumatic stress disorder-like behaviours, and forebrain dFosB expression, in rats', Neuroscience, 169 733-742 (2010) [C1]|
|2010||Tynan R, Naicker S, Hinwood M, Nalivaiko E, Buller KM, Pow DV, et al., 'Chronic stress alters the density and morphology of microglia in a subset of stress-responsive brain regions', Brain Behavior and Immunity, 24 1058-1068 (2010) [C1]|| |
|2010||Baumert M, Seeck A, Faber R, Nalivaiko E, Voss A, 'Longitudinal changes in QT interval variability and rate adaptation in pregnancies with normal and abnormal uterine perfusion', Hypertension Research, 33 555-560 (2010) [C1]|| |
|2010||Nalivaiko E, Antunes VR, Paton JFR, 'Control of cardiac contractility in the rat working heart-brainstem preparation', Experimental Physiology, 95 107-119 (2010) [C1]|| |
|2009||Nalivaiko E, Mastorci F, Sgoifo A, '8-OH-DPAT prevents cardiac arrhythmias and attenuates tachycardia during social stress in rats', Physiology and Behavior, 96 320-327 (2009) [C1]|| |
|2009||Mastorci F, Vicentini M, Viltart O, Manghi M, Graiani G, Quaini F, et al., 'Long-term effects of prenatal stress: Changes in adult cardiovascular regulation and sensitivity to stress', Neuroscience & Biobehavioral Reviews, 33 191-203 (2009) [C1]|| |
|2009||Nalivaiko E, Sgoifo A, 'Central 5-HT receptors in cardiovascular control during stress', Neuroscience & Biobehavioral Reviews, 33 95-106 (2009) [C1]|| |
|2009||Beig MI, Baumert M, Walker FR, Day TA, Nalivaiko E, 'Blockade of 5-HT2A receptors suppresses hyperthermic but not cardiovascular responses to psychosocial stress in rats', Neuroscience, 159 1185-1191 (2009) [C1]|| |
|2009||Xavier CH, Nalivaiko E, Beig MI, Menezes GB, Cara DC, Campagnole-Santos MJ, Fontes MAP, 'Functional asymmetry in the descending cardiovascular pathways from dorsomedial hypothalamic nucleus', Neuroscience, 164 1360-1368 (2009) [C1]|| |
|2009||Salo LM, Nalivaiko E, Anderson CR, McAllen RM, 'Control of cardiac rate, contractility, and atrioventricular conduction by medullary raphe neurons in anesthetized rats', American Journal of Physiology-Heart and Circulatory Physiology, 296 H318-H324 (2009) [C1]|| |
|2009||Baumert M, Lambert GW, Dawood T, Lambert EA, Esler MD, McGrane M, et al., 'Short-term heart rate variability and cardiac norepinephrine spillover in patients with depression and panic disorder', American Journal of Physiology: Heart and Circulatory Physiology, 297 H674-H679 (2009) [C1]|| |
|2009||Smith JH, Baumert M, Nalivaiko E, McEvoy RD, Catcheside PG, 'Arousal in obstructive sleep apnoea patients is associated with ECG RR and QT interval shortening and PR interval lengthening', Journal of Sleep Research, 18 188-195 (2009) [C1]|| |