Carta Revisado por pares

Increased mechanoreceptor/metaboreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure

2007; American Physiological Society; Volume: 102; Issue: 1 Linguagem: Inglês

10.1152/japplphysiol.01247.2006

ISSN

8750-7587

Autores

Irving H. Zucker, Harold D. Schultz, Wei Wang,

Tópico(s)

Cardiovascular Effects of Exercise

Resumo

POINT-COUNTERPOINT COMMENTSIncreased mechanoreceptor/metaboreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failureIrving H. Zucker, Harold D. Schultz, and Wei WangIrving H. Zucker, Harold D. Schultz, and Wei WangPublished Online:01 Jan 2007https://doi.org/10.1152/japplphysiol.01247.2006MoreSectionsPDF (51 KB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat The following letters are in response to the Point:Counterpoint series “Increased mechanoreceptor/metaboreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure” that appears in this issue.To the Editor: The Point:Counterpoint concerning the issue of mechanoreceptor vs. metaboreceptor control of sympathetic nerve activity (SNA) in chronic heart failure (CHF; Refs. 1, 2) relates exclusively to input from exercising skeletal muscle. Although both sides make cogent points on the basis of published data, in our opinion the debate has not been conclusively settled and will not be using the types of experiments carried out in human subjects. First, it is certainly not clear if passive exercise simulates true dynamic exercise and, second, if capsaicin injections simulate the ischemic stimulus observed during exercise in the CHF state. We offer an alternative hypothesis as to the mechanism for exaggerated SNA during exercise in the CHF state. Clearly exercise evokes a stimulus from muscle but also may increase neural signaling from cardiac and chemoreflexes in the heart and in the arterial system. Cardiac sympathetic afferents respond to ischemic metabolites, which are likely to be elevated in CHF patients during exercise. These largely c-fiber afferents are sensitized in animals with CHF (5). The cardiac sympathetic afferent reflex is clearly augmented in CHF (6). In addition to this particular sympathoexcitatory reflex, the arterial chemoreflex is sensitized in CHF (3). It is not inconceivable that carotid hypoxia during exercise (perhaps as a result of pulmonary interstitial edema) evoking an increase in carotid body activity acts as another sympathoexcitatory reflex. Because both of these afferent pathways appear to be enhanced even under normoxic resting conditions and because our recent data indicate that these inputs to the nucleus of the solitary tract augment sympathoexcitatory stimuli (4), they can not be excluded as potential contributors to the exaggerated SNA responses to exercise.REFERENCES1 Middlekauf HR, Sinoway LI. Point: Increased mechanoreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure. J Appl Physiol. In press.Google Scholar2 Piepoli MF, Coats AJS. Counterpoint: Increased metaboreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure. J Appl Physiol. In press.Google Scholar3 Sun SY, Wang W, Zucker IH, Schultz HD. Enhanced peripheral chemoreflex function in conscious rabbits with pacing-induced heart failure. J Appl Physiol 86: 1264–1272, 1999.Link | ISI | Google Scholar4 Wang WZ, Gao L, Pan YX, Zucker IH, Wang W. Differential effects of cardiac sympathetic afferent stimulation on neurons in the nucleus tractus solitarius. Neurosci Lett. In press.Google Scholar5 Wang W, Zucker IH. Cardiac sympathetic afferent reflex in dogs with congestive heart failure. Am J Physiol Regul Integr Comp Physiol 271: R751–R756, 1996.Link | ISI | Google Scholar6 Zhu GQ, Zucker IH, Wang W. Central AT1 receptors are involved in the enhanced cardiac sympathetic afferent reflex in rats with chronic heart failure. Basic Res Cardiol 97: 320–326, 2002.Crossref | PubMed | ISI | Google ScholarjapJ Appl PhysiolJournal of Applied PhysiologyJ Appl Physiol8750-75871522-1601American Physiological SocietyjapJ Appl PhysiolJournal of Applied PhysiologyJ Appl Physiol8750-75871522-1601American Physiological SocietyjapJ Appl PhysiolJournal of Applied PhysiologyJ Appl Physiol8750-75871522-1601American Physiological SocietyjapJ Appl PhysiolJournal of Applied PhysiologyJ Appl Physiol8750-75871522-1601American Physiological SocietyjapJ Appl PhysiolJournal of Applied PhysiologyJ Appl Physiol8750-75871522-1601American Physiological SocietyjapJ Appl PhysiolJournal of Applied PhysiologyJ Appl Physiol8750-75871522-1601American Physiological SocietyjapJ Appl PhysiolJournal of Applied PhysiologyJ Appl Physiol8750-75871522-1601American Physiological SocietyPoint:Counterpoint CommentsMarco GuazziUniversity of MilanoJanuary2007Point:Counterpoint CommentsAdam C. ScottRoyal Brisbane and Women's HospitalJanuary2007Point:Counterpoint CommentsCarlos E. Negrao, and Maria U. P. B. RondonHeart Institute Medical School and School of Physical Education and Sport University São Paulo, BrazilJanuary2007Point:Counterpoint CommentsE. Sankaranarayanan PrakashSchool of Medicine Asian Institute of Medicine, Science and Technology Kedah, MalaysiaJanuary2007Point:Counterpoint CommentsAndrew L. ClarkAcademic Cardiology Castle Hill Hospital Hull, United KingdomJanuary2007Point:Counterpoint CommentsAntonio Crisafulli, and Alberto ConcuUniversity of CagliariJanuary2007Point:Counterpoint CommentsCharlotte H. Manisty, and Darrel P. FrancisInternational Centre for Circulatory Health St. Mary's Hospital and Imperial College London, United KingdomJanuary2007To the Editor: Because endothelium modulates exercise neurogenic vasoconstriction and upregulates muscle perfusion (1), diseases causing endothelial dysfunction (ED) are conceivably associated with exercising muscle hypoperfusion and local overproduction of metabolic by-products that trigger the exercise pressor reflex. Hence, ED in CHF (4) might be a reason for muscle oversignalling, and CHF might not be the only condition eliciting overstimulation of skeletal muscle neural afferents. Atrial fibrillation (AF) is a model suitable to verify these possibilities, because it is associated with endothelial oxidative injury and endothelial function recovers with cardioversion (CV) or antioxidant vitamin C (2, 3). In lone atrial fibrillation we found that after vitamin C and following CV, the endothelial brachial artery flow-mediated dilatation (FMD) increased and the ergoreflex component of the ventilatory response to handgrip (EVR) and the slope of ventilation to V̇co2 production (V̇e/V̇co2) significantly reduced. In AF associated with diabetes (additive endothelial impairment), no changes in EVR and V̇e/V̇co2 slope occurred after CV and FMD was refractory to either intervention (3). Ventilatory inefficiency (steep V̇e/V̇co2 slope) and a low arterial co2 pressure to incremental exercise occur in AF and both are brought back to normal by CV (2). Since arterial O2 saturation was normal and unaffected by CV, a reasonable explanation for a less-efficient ventilation is an intervention of extrapulmonary peripheral factors (2, 3). These results altogether are consistent with the thesis of an increased mechanoreceptor activity (5) and strengthen the thesis of an increased metaboreceptor activity (6). The same may be true of CHF. To the Editor: Middlekauf and Sinoway (2) present an intriguing argument for mechanoreceptor activation having a more profound effect on the exercise pressor reflex (EPR) in heart failure (HF) than the role of metaboreceptor activity. Their main argument is based on animal experiments, which do not simulate human heart failure. De Meersman and colleagues (1) presented some interesting data on passive limb movement showing an increase in V̇o2 of almost 90% the size of the increase produced by active unloaded exercise. This study supports several other group findings that indicate more elaborate and sensitive testing is required to further examine this reflex. We are aware that the mechanoreflex has a role in stimulating the EPR, but the extent of its role is less than the metaboreflex (3).Piepoli and Coats (4) provide a thorough background into the established “skeletal muscle hypothesis.” Their defense, or offence, of the metaboreceptor and its role with the EPR is supported by complete studies with reproducible results. The metaboreflex is very well supported; the degree of receptor dominance does need to be investigated with testing protocols that are consistent and on HF patients that indeed are significantly classified as human HF. Piepoli and Coats provide an in-depth assessment of the issue at hand, including the pathophysiological (“skeletal muscle hypothesis”) and therapeutic (exercise training beneficial effect) implication. Instead, Middlekauf and Sinoway provide no background for why the mechanoreflex is dominant in their eyes: it is difficult to defend their position without clear evidence of the physiological inference.To the Editor: We read the debate between Drs. Middlekauff and Sinoway and Drs. Piepoli and Coats on the exercise pressure response (EPR) in heart failure (HF) with great interest. We want to thank these investigators for providing us with such an outstanding discussion regarding sensory muscle fibers, which are responsible for the reflex abnormalities during exercise in HF patients. Both sides have relevant arguments for the role of the muscle mechanoreceptors and metaboreceptors in the exaggerated EPR in HF (1, 2, 4). However, we are convinced that the increased mechanoreceptor activity explains the augmented EPR in HF patients. The significant increase in muscle sympathetic nerve activity (MSNA) during passive exercise (2) and low-intensity exercise (10% MVC; Ref. 3) and the augmented renal vascular resistance during mechanoreceptor stimulation (1) strongly favor the increased mechanoreceptor activity in HF patients. On the other hand, it is unlikely that the increased muscle metaboreceptor activity is responsible for exaggerated EPR in HF. Different groups have shown that, during post-exercise muscle circulatory arrest, when the metaboreceptors are isolated from central command and mechanoreceptors, MSNA remains elevated in healthy individuals, whereas in HF patients it returns to baseline (3, 6). These findings demonstrate that the muscle metaboreceptor sensitivity is reduced in HF patients. In addition, the argument that muscle circulatory arrest also stimulates nociceptive neurons is unfounded. A recent study showed that 2 min of this maneuver after 3 min in a quiet resting position caused no changes in MSNA and mean BP levels when compared with baseline in normotensive individuals and hypertensive patients (5).To the Editor: The conclusion by Middlekauff and Sinoway (3) that “the metaboreflex is blunted in heart failure” is unjustified because the contribution of this reflex to elevations in baseline muscle sympathetic nerve activity (MSNA) in heart failure has not been evaluated. Because MSNA is elevated at rest in low cardiac output heart failure, it is possible that (as suggested in Ref. 1) at least in severe heart failure, the metaboreflex is nearly saturatingly recruited at rest, and this may be why their additional contribution to the exercise pressor response (EPR) is attenuated. In contrast, an increase in MSNA (2-tailed P = 0.07, based on data in Table 1, Ref. 5) occurred only during the second minute of static forearm exercise in control subjects, suggesting that the metaboreflex was recruited only then.Second, endothelial function defective in its vasodilator capacity likely explains why the vasoconstricting effect (especially in exercising skeletal muscle) of an elevation in MSNA during exercise is exaggerated in heart failure (also noted by Guazzi in response to this call for comments). Endothelium-dependent and endothelium-independent vasodilation is impaired in patients with even mild heart failure (2).Finally, in references 12–16 and 18 of Middlekauff and Sinoway's article (3), the authors of the cited studies did not specifically distinguish muscle mechanoreceptor and metaboreceptor contributions to the EPR but have collectively used the term metaboreceptors (or ergoreceptors) to refer to both of them. Thus Middlekauff and Sinoway (3) are mistaken in inferring these results as contradicting with theirs.To the Editor: I much enjoyed reading both sides of the debate between Piepoli and Coats (4) on the one hand and Middlekauff and Sinoway (2) on the other. It is encouraging to see ever-widening acceptance of the “muscle hypothesis” for the explanation of symptoms in chronic heart failure (1). The present debate between the protagonists is akin to that between Big-Endians and Little-Endians in Gulliver's Travels (6); there is little profound difference between the two sides, and both take for granted that the muscle hypothesis is correct.Neither side of the debate, however, convincingly deals with the other's key points. There is no convincing explanation for the apparent blunting of the metaboreflex in heart failure seen in sympathetic nerve activity recordings from Piepoli and Coats (4) and, equally, no convincing explanation for the enhanced metaboreflex demonstrated when considering ventilatory responses to exercise from Middlekauff and Sinoway (2) despite the fact that both sets of experiments used a similar design of exercise with postexercise regional circulatory occlusion.Although it might be uncomfortable for both sides to accept, a possible resolution to the debate is to accept that although the periphery does indeed drive exercise responses, the exercise response (like many other systems in the body) is marked by duplication and redundancy. It is surely possible—indeed, as the present debate makes clear, probable—that different aspects of the exercise response are predominantly driven by different aspects of the peripheral response: the sympathetic response might be driven predominantly be mechanoreflexes and the ventilatory response by metaboreceptors.To the Editor: In this Point:Counterpoint, two opposite theses have been exposed to explain the exaggerated exercise pressor reflex in heart failure (HF): metaboreceptor vs. mechanoreceptors overactivation (4, 6). Both theories agree that a sympathetic overdrive originating from muscular receptors occurs during effort, and the only real difference between the two opponents is the muscular receptor being activated. However, both theories do not take into account the effect of the activation of these receptors on central hemodynamics. We demonstrated that the metaboreflex engagement obtained by postexercise muscle ischemia (PEMI) can elicit substantial enhancement in cardiac performance in healthy individuals (1, 2). The PEMI maneuver clearly rules out any contribution of mechanoreceptors to this contractility response because mechanoreceptors are not operating in this setting. Moreover, circulatory occlusion without previous exercise (i.e., without metabolic end-products accumulation within muscle) did not cause any relevant hemodynamic consequence (1, 2). Thus, in normal subjects, a myocardial contractility modulation is possible via metaboreflex recruitment. However, the possibility that metaboreflex can still evoke a contractility response in HF patients has never been investigated, although recent studies conducted on animal models of HF suggest that the limited capacity to enhance ventricular performance is responsible for a functional shift from cardiac output to systemic vascular resistance increase in the mechanism by which the cardiovascular system responds to metaboreflex (3, 5). Thus it appears that the hemodynamic disarrangement shown by HF patients may also derive from the incapacity of the failing circulation to increase contractility in response to metaboreflex.To the Editor: In this Point:Counterpoint discussion on the relative role of the mechanoreceptor and metaboreceptor reflexes in the enhanced skeletal pressor responses found in heart failure (HF; Refs. 3, 4), both discussants accept the importance of skeletal muscle afferents. While Middlekauff and Sinoway use animal models to argue that pharmacological inhibition of mechanoreceptor stimulation results in elimination of the pressor response seen in HF, this does not completely mimic human physiology. They cite human data from their own laboratory showing that the pressor response during low-level rhythmic exercise in HF patients was measurable earlier than in normal subjects (2), which they argue may signify an enhanced mechanoceptor response. However, this may simply reflect a lower threshold for activation of the metaboreflex in HF subjects than normals (1), and they also concede that this activity will also stimulate metaboreceptors.Piepoli and Coats and colleagues (4, 5) present the case for enhanced metaboreceptor sensitivity having attempted to clinically separate the two types of receptor in humans. Although they found it impossible to entirely eliminate the mechanoreceptor response despite using only passive exercise, they clearly demonstrated the significantly greater contribution from the metaboreceptor than the mechanoreceptor.What is clear from the clinical experiments cited by both authors is that complete separation of the two types of muscle stimulus is difficult in normal subjects, and using current methodology this question seems set to remain unresolved. One wonders whether studying patients with reduced muscular tone (either secondary to neurological disease or muscle relaxants given during general anesthesia) may add useful information to this debate.REFERENCES1. Engelke KA, Williams MM, Dietz NM, Joyner MJ. Does sympathetic activation blunt nitric oxide mediated hyperemia in the human forearm? Clin Auton Res 7: 85–51, 1997. Crossref | PubMed | ISI | Google Scholar2. Guazzi M, Belletti S, Tumminello G, Fiorentini C, Guazzi MD. Exercise hyperventilation, dyspnea sensation and ergoreflex activation in lone atrial fibrillation. Am J Physiol Heart Circ Physiol 287: H2899–H2905, 2004. Link | ISI | Google Scholar3. Guazzi M, Berti M, Belletti S, Reina G, Guazzi MD. Exercise metaboreflex activation and endothelial function impairment in atrial fibrilation. Am J Physiol Heart Circ Physiol 291: H2396–H2402, 2006. Link | ISI | Google Scholar4. Katz SD, Balidemai K, Homma S, Wu H, Wang J, Maybaum S. Acute type 5 phosphodiesterase inhibition with sildenafil enhances flow-mediated vasodilatation in patients with chronic heart failure. J Am Coll Cardiol 36: 845–851, 2000. Crossref | PubMed | ISI | Google Scholar5. Middlekauf HR, Sinoway LI. Point: Increased mechanoreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure. J Appl Physiol. In press. Google Scholar6. Piepoli MF, Coats AJS. Counterpoint: Increased metaboreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure. J Appl Physiol. In press. Google ScholarREFERENCES1. De Meersman RE, Zion AS, Weir JP, Lieberman JS, Downey JA. Mechanoreceptors and autonomic responses to movement in humans. Clin Auton Res 8: 201–205, 1998. Crossref | ISI | Google Scholar2. Middlekauf HR, Sinoway LI. Point: Increased mechanoreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure. J Appl Physiol. In press. Google Scholar3. Piepoli MF, Coats AJS. Counterpoint: Increased metaboreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure. J Appl Physiol. In press. Google Scholar4. Scott AC, Francis DP, Davies LC, Ponikowski P, Coats AJS, Piepoli MF. Contribution of skeletal muscle “ergoreceptors” in the human leg to respiratory control in chronic heart failure. J Physiol 529.3: 863–870, 2000. ISI | Google ScholarREFERENCES1. Middlekauff HR, Sinoway LI. Point: Increased mechanoreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure. J Appl Physiol. In press. Google Scholar2. Middlekauff HR, Chiu J, Hamilton MA, Fonarow GC, Maclellan WR, Hage A, Moriguchi J, Patel J. Muscle mechanoreceptor sensitivity in heart failure. Am J Physiol Heart Circ Physiol 287: H1937–H1943, 2004. Link | ISI | Google Scholar3. Negrao CE, Rondon MU, Tinucci T, Alves MJ, Roveda F, Braga AM, Reis SF, Nastari L, Barretto AC, Krieger EM, Middlekauff HR. Abnormal neurovascular control during exercise is linked to heart failure severity. Am J Physiol Heart Circ Physiol 280: H1286–H1292, 2001. Link | ISI | Google Scholar4. Piepoli MF, Coats AJS. Counterpoint: Increased metaboreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure. J Appl Physiol. In press. Google Scholar5. Rondon MU, Laterza MC, de Matos LD, Trombetta IC, Braga AM, Roveda F, Alves MJ, Krieger EM, Negrao CE. Abnormal muscle metaboreflex control of sympathetic activity in never-treated hypertensive subjects. Am J Hypertens 19: 951–957, 2006. Crossref | PubMed | ISI | Google Scholar6. Sterns DA, Ettinger SM, Gray KS, Whisler SK, Mosher TJ, Smith MB, Sinoway LI. Skeletal muscle metaboreceptor exercise responses are attenuated in heart failure. Circulation 84: 2034–2039, 1991. Crossref | PubMed | ISI | Google ScholarREFERENCES1. Hammond RL, Augustyniak RA, Rossi NF, Churchill PC, Lapanowski K, Leary DSO. Heart failure alters the strength and mechanisms of the muscle metaboreflex. Am J Physiol Heart Circ Physiol 278: H818–H828, 2000. Link | ISI | Google Scholar2. Heitzer T, Baldus S, Kodolitsch YV, Rudolph V, Meinertz T. Systemic endothelial dysfunction as an early predictor of adverse outcome in heart failure. Arterioscler Thromb Vasc Biol 25: 1174–1179, 2005. Crossref | PubMed | ISI | Google Scholar3. Middlekauff HR, Sinoway LI. Point: Increased mechanoreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure. J Appl Physiol. In press. Google Scholar4. Piepoli MF, Coats AJS. Counterpoint: Increased metaboreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure. J Appl Physiol. In press. Google Scholar5. Sterns DA, Ettinger SM, Gray KS, Whisler SK, Mosher TJ, Smith MB, Sinoway LI. Skeletal muscle metaboreceptor exercise responses are attenuated in heart failure. Circulation 84: 2034–2039, 1991. Crossref | PubMed | ISI | Google ScholarREFERENCES1. Coats AJ, Clark AL, Piepoli M, Volterrani M, Poole-Wilson PA. Symptoms and quality of life in heart failure: the muscle hypothesis. Br Heart J 72: S36–S39, 1994. Crossref | PubMed | Google Scholar2. Middlekauff HR, Sinoway LI. Point: Increased mechanoreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure. J Appl Physiol. In press. Google Scholar3. Piepoli M, Clark AL, Volterrani M, Adamopoulos S, Sleight P, Coats AJS. Contribution of muscle afferents to the hemodynamic, autonomic, and ventilatory responses to exercise in patients with chronic heart failure. Effects of physical training. Circulation 93: 940–952, 1996. Crossref | PubMed | ISI | Google Scholar4. Piepoli MF, Coats AJS. Counterpoint: Increased metaboreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure. J Appl Physiol. In press. Google Scholar5. Sterns DA, Ettinger SM, Gray KS, Whisler SK, Mosher TJ, Smith MB, Sinoway LI. Skeletal muscle metaboreceptor exercise responses are attenuated in heart failure. Circulation 84: 2034–2039, 1991. Crossref | PubMed | ISI | Google Scholar6. Swift J. Travels into Several Remote Nations of the World. London, 1726. Google ScholarREFERENCES1. Crisafulli A, Scott AC, Wensel R, Davos CH, Francis DP, Pagliaro P, Coats AJS, Concu A, Piepoli MF. Muscle metaboreflex-induced increases in stroke volume. Med Sci Sports Exerc 35: 221–228, 2003. Crossref | PubMed | ISI | Google Scholar2. Crisafulli A, Salis E, Pittau G, Lorrai L, Tocco F, Melis F, Pagliaro P, Concu A. Modulation of cardiac contractility by muscle metaboreflex following efforts of different intensities in humans. Am J Physiol Heart Circ Physiol [Jun 2006; doi:10.1152/ajpheart.00221.2006]. Google Scholar3. Hammond RL, Augustyniak RA, Rossi NF, Churchill PC, Lapanowsky K, O'Leary DS. Heart failure alters the strength and mechanisms of the muscle metaboreflex. Am J Physiol Heart Circ Physiol 278: H818–H828, 2000. Link | ISI | Google Scholar4. Middlekauff HR, Sinoway LI. Point: Increased mechanoreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure. J Appl Physiol. In press. Google Scholar5. O'Leary DS, Sala-Mercado JA, Augustyniak RA, Hammond RL, Rossi NF, Ansorge EJ. Impaired muscle metaboreflex-induced increases in ventricular function in heart failure. Am J Physiol Heart Circ Physiol 287: H2612–H2618, 2004. Link | ISI | Google Scholar6. Piepoli MF, Coats AJS. Counterpoint: Increased metaboreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure. J Appl Physiol. In press. Google ScholarREFERENCES1. Augustyniak RA, Ansorge EJ, Kim JK, Sala-Mercado JA, Hammond RL, Rossi NF, O'Leary DS. Cardiovascular responses to exercise and muscle metaboreflex activation during the recovery from pacing-induced heart failure. J Appl Physiol 101: 14–22, 2006. Link | ISI | Google Scholar2. Middlekauff HR, Chiu J, Hamilton MA, Fonarow GC, MacLellan WR, Hage A, Moriguchi J, Patel J. Muscle mechanoreceptor sensitivity in heart failure. Am J Physiol Heart Circ Physiol 287: H1937–H1943, 2004. Link | ISI | Google Scholar3. Middlekauff HR, Sinoway LI. Point: Increased mechanoreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure. J Appl Physiol. In press. Google Scholar4. Piepoli M, Coats AJ. Counterpoint: Increased metaboreceptor stimulation explains the exaggerated exercise pressor reflex seen in heart failure. J Appl Physiol. In press. Google Scholar5. Scott AC, Francis DP, Davies LC, Ponikowski P, Coats AJS, Piepoli MF. Contribution of skeletal muscle “ergoreceptors” in the human leg to respiratory control in chronic heart failure. J Physiol 529: 863–870, 2000. Crossref | PubMed | ISI | Google Scholar Download PDF Previous Back to Top Next FiguresReferencesRelatedInformationCited ByWalking With Leg Blood Flow Restriction: Wide-Rigid Cuffs vs. Narrow-Elastic Bands29 May 2020 | Frontiers in Physiology, Vol. 11Cardiovascular and ventilatory control during exercise in chronic heart failure: Role of muscle reflexesInternational Journal of Cardiology, Vol. 130, No. 1Impaired central hemodynamic response and exaggerated vasoconstriction during muscle metaboreflex activation in heart failure patientsAntonio Crisafulli, Enrico Salis, Filippo Tocco, Franco Melis, Raffaele Milia, Gianluigi Pittau, Marcello A. Caria, Roberto Solinas, Luigi Meloni, Pasquale Pagliaro, and Alberto Concu1 June 2007 | American Journal of Physiology-Heart and Circulatory Physiology, Vol. 292, No. 6 More from this issue > Volume 102Issue 1January 2007Pages 498-501 Copyright & PermissionsCopyright © 2007 the American Physiological Societyhttps://doi.org/10.1152/japplphysiol.01247.2006PubMed17209163History Published online 1 January 2007 Published in print 1 January 2007 Metrics

Referência(s)