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Central nervous system circuits modified in heart failure: pathophysiology and therapeutic implications. Heart Fail Rev 2015; 19:759-79. [PMID: 24573960 DOI: 10.1007/s10741-014-9427-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The pathophysiology of heart failure (HF) is characterized by an abnormal activation of neurohumoral systems, including the sympathetic nervous and the renin-angiotensin-aldosterone systems, which have long-term deleterious effects on the disease progression. Perpetuation of this neurohumoral activation is partially dependent of central nervous system (CNS) pathways, mainly involving the paraventricular nucleus of the hypothalamus and some regions of the brainstem. Modifications in these integrative CNS circuits result in the attenuation of sympathoinhibitory and exacerbation of sympathoexcitatory pathways. In addition to the regulation of sympathetic outflow, these central pathways coordinate a complex network of agents with an established pathophysiological relevance in HF such as angiotensin, aldosterone, and proinflammatory cytokines. Central pathways could be potential targets in HF therapy since the current mainstay of HF pharmacotherapy aims primarily at antagonizing the peripheral mechanisms. Thus, in the present review, we describe the role of CNS pathways in HF pathophysiology and as potential novel therapeutic targets.
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Silva MPD, Cedraz-Mercez PL, Varanda WA. Effects of nitric oxide on magnocellular neurons of the supraoptic nucleus involve multiple mechanisms. Braz J Med Biol Res 2014; 47:90-100. [PMID: 24519124 PMCID: PMC4051181 DOI: 10.1590/1414-431x20133326] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 10/22/2013] [Indexed: 01/24/2023] Open
Abstract
Physiological evidence indicates that the supraoptic nucleus (SON) is an
important region for integrating information related to homeostasis of body
fluids. Located bilaterally to the optic chiasm, this nucleus is composed of
magnocellular neurosecretory cells (MNCs) responsible for the synthesis and
release of vasopressin and oxytocin to the neurohypophysis. At the cellular
level, the control of vasopressin and oxytocin release is directly linked to the
firing frequency of MNCs. In general, we can say that the excitability of these
cells can be controlled via two distinct mechanisms: 1) the intrinsic membrane
properties of the MNCs themselves and 2) synaptic input from circumventricular
organs that contain osmosensitive neurons. It has also been demonstrated that
MNCs are sensitive to osmotic stimuli in the physiological range. Therefore, the
study of their intrinsic membrane properties became imperative to explain the
osmosensitivity of MNCs. In addition to this, the discovery that several
neurotransmitters and neuropeptides can modulate their electrical activity
greatly increased our knowledge about the role played by the MNCs in fluid
homeostasis. In particular, nitric oxide (NO) may be an important player in
fluid balance homeostasis, because it has been demonstrated that the enzyme
responsible for its production has an increased activity following a hypertonic
stimulation of the system. At the cellular level, NO has been shown to change
the electrical excitability of MNCs. Therefore, in this review, we focus on some
important points concerning nitrergic modulation of the neuroendocrine system,
particularly the effects of NO on the SON.
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Affiliation(s)
- M P da Silva
- Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão PretoSP, Brasil, Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brasil
| | - P L Cedraz-Mercez
- Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão PretoSP, Brasil, Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brasil
| | - W A Varanda
- Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão PretoSP, Brasil, Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brasil
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Nomura M, Tsutsui M, Shimokawa H, Fujimoto N, Ueta Y, Morishita T, Yanagihara N, Matsumoto T. Effects of nitric oxide synthase isoform deletion on oxytocin and vasopressin messenger RNA in mouse hypothalamus. Neuroreport 2005; 16:413-7. [PMID: 15729148 DOI: 10.1097/00001756-200503150-00021] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The effects of neuronal, endothelial, or inducible nitric oxide synthase gene disruption on the expression of oxytocin and vasopressin gene were examined in the hypothalamus (paraventricular, supraoptic, suprachiasmatic, and anterior commissural nuclei) and extrahypothalamus (bed nucleus of the stria terminalis). The oxytocin messenger RNA levels in the anterior commissural nucleus of neuronal nitric oxide synthase knockout mice were significantly higher than in control mice, but not in endothelial or inducible nitric oxide synthase knockout mice. In contrast, no significant effects of neuronal, endothelial, or inducible nitric oxide synthase gene disruption on oxytocin and vasopressin messenger RNA levels in the other hypothalamic and extrahypothalamic nuclei were observed. These results suggest that neuronal nitric-oxide-synthase-derived nitric oxide may be involved in the regulation of oxytocin gene expression in the anterior commissural nucleus.
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Affiliation(s)
- Masayoshi Nomura
- Department of Urology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan.
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Abstract
On one side, brain dysfunction is a poorly explored complication of sepsis. On the other side, brain dysfunction may actively contribute to the pathogenesis of sepsis. The current review aimed at summarizing the current knowledge about the reciprocal interaction between the immune and central nervous systems during sepsis. The immune-brain cross talk takes part in circumventricular organs that, being free from blood-brain-barrier, interface between brain and bloodstream, in autonomic nuclei including the vagus nerve, and finally through the damaged endothelium. Recent observations have confirmed that sepsis is associated with excessive brain inflammation and neuronal apoptosis which clinical relevance remains to be explored. In parallel, damage within autonomic nervous and neuroendocrine systems may contribute to sepsis induced organ dysfunction.
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Affiliation(s)
- Tarek Sharshar
- Attending Physician, Service de Réanimation Médicale, Hôpital Raymond Poincaré, Faculté de Médecine Paris Ile de France Ouest, Université de Versailles Saint-Quentin-en-Yvelines, Garches, France
| | - Nicholas S Hopkinson
- Attending Physician, Respiratory Muscle Laboratory, Royal Brompton and Harefield NHS Trust, Fulham Road, London, SW3 6NP, United Kingdom
| | - David Orlikowski
- Attending Physician, Service de Réanimation Médicale, Hôpital Raymond Poincaré, Faculté de Médecine Paris Ile de France Ouest, Université de Versailles Saint-Quentin-en-Yvelines, Garches, France
| | - Djillali Annane
- Head of ICU Department, Service de Réanimation Médicale, Hôpital Raymond Poincaré, Faculté de Médecine Paris Ile de France Ouest, Université de Versailles Saint-Quentin-en-Yvelines, Garches, France
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Stern JE, Zhang W. Cellular sources, targets and actions of constitutive nitric oxide in the magnocellular neurosecretory system of the rat. J Physiol 2004; 562:725-44. [PMID: 15550458 PMCID: PMC1665550 DOI: 10.1113/jphysiol.2004.077735] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Nitric oxide (NO) is a key activity-dependent modulator of the magnocellular neurosecretory system (MNS) during conditions of high hormonal demand. In addition, recent studies support the presence of a functional constitutive NO tone. The aim of this study was to identify the cellular sources, targets, signalling mechanisms and functional relevance of constitutive NO production within the supraoptic nucleus (SON). Direct visualization of intracellular NO, along with neuronal nitric oxide synthase (nNOS) and cGMP immunohistochemistry, was used to study the cellular sources and targets of NO within the SON, respectively. Our results support the presence of a strong NO basal tone within the SON, and indicate that vasopressin (VP) neurones constitute the major neuronal source and target of basal NO. NO induced-fluorescence and cGMP immunoreactivity (cGMPir) were also found in the glia and microvasculature of the SON, suggesting that they contribute as sources/targets of NO within the SON. cGMPir was also found in association with glutamic acid decarboxylase 67 (GAD67)- and vesicular glutamate transporter 2 (VGLUT2)-positive terminals. Glutamate, acting on NMDA and possibly AMPA receptors, was found to be an important neurotransmitter driving basal NO production within the SON. Finally, electrophysiological recordings obtained from SON neurones in a slice preparation indicated that constitutive NO efficiently restrains ongoing firing activity of these neurones. Furthermore, phasically active (putative VP) and continuously firing neurones appeared to be influenced by NO originating from different sources. The potential roles for basal NO as an autocrine signalling molecule, and one that bridges neuronal-glial-vascular interactions within the MNS are discussed.
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Affiliation(s)
- Javier E Stern
- Department of Psychiatry, Genome Research Insitute, University of Cincinnati, 2170 E. Galbraith Road, Cincinnati, OH 45237, USA.
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Antunes-Rodrigues J, de Castro M, Elias LLK, Valença MM, McCann SM. Neuroendocrine control of body fluid metabolism. Physiol Rev 2004; 84:169-208. [PMID: 14715914 DOI: 10.1152/physrev.00017.2003] [Citation(s) in RCA: 336] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Mammals control the volume and osmolality of their body fluids from stimuli that arise from both the intracellular and extracellular fluid compartments. These stimuli are sensed by two kinds of receptors: osmoreceptor-Na+ receptors and volume or pressure receptors. This information is conveyed to specific areas of the central nervous system responsible for an integrated response, which depends on the integrity of the anteroventral region of the third ventricle, e.g., organum vasculosum of the lamina terminalis, median preoptic nucleus, and subfornical organ. The hypothalamo-neurohypophysial system plays a fundamental role in the maintenance of body fluid homeostasis by secreting vasopressin and oxytocin in response to osmotic and nonosmotic stimuli. Since the discovery of the atrial natriuretic peptide (ANP), a large number of publications have demonstrated that this peptide provides a potent defense mechanism against volume overload in mammals, including humans. ANP is mostly localized in the heart, but ANP and its receptor are also found in hypothalamic and brain stem areas involved in body fluid volume and blood pressure regulation. Blood volume expansion acts not only directly on the heart, by stretch of atrial myocytes to increase the release of ANP, but also on the brain ANPergic neurons through afferent inputs from baroreceptors. Angiotensin II also plays an important role in the regulation of body fluids, being a potent inducer of thirst and, in general, antagonizes the actions of ANP. This review emphasizes the role played by brain ANP and its interaction with neurohypophysial hormones in the control of body fluid homeostasis.
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Affiliation(s)
- José Antunes-Rodrigues
- Department of Physiology, School of Medicine of Ribeirao Preto, University of São Paulo, Ribeirao Preto, São Paulo, Brazil.
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El-Haddad MA, Chao CR, Ma SX, Ross MG. Neuronal NO modulates spontaneous and ANG II-stimulated fetal swallowing behavior in the near-term ovine fetus. Am J Physiol Regul Integr Comp Physiol 2002; 282:R1521-7. [PMID: 11959696 DOI: 10.1152/ajpregu.00229.2001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Spontaneous fetal swallowing occurs at a markedly higher rate compared with spontaneous adult drinking activity. This high rate of fetal swallowing is critical for amniotic fluid volume regulation. Central NO is critical for maintaining the normal rate of fetal swallowing, as nonselective inhibition of NO (with central N(G)-nitro-L-arginine methyl ester) suppresses spontaneous and angiotensin II (ANG II)-stimulated swallowing. We sought to differentiate the contributions of central endothelial vs. neuronal NO in the regulation of spontaneous and stimulated fetal swallowing, using a selective neuronal NO synthase (nNOS) inhibitor. Six time-dated pregnant ewes and fetuses were chronically prepared with fetal vascular and intracerebroventricular (i.c.v.) catheters and electrocorticogram (ECoG) and esophageal electromyogram electrodes and studied at 130 +/- 1 days of gestation. After an initial 2-h baseline period (0-2 h), the selective nNOS inhibitor N-propyl-L-arginine (NPLA) was injected i.c.v. (2-4 h). At 4 h, the dose of NPLA was repeated, together with ANG II, and fetal swallowing was monitored for a final 2 h. Four fetuses also received an identical control study (on an alternate day) in which NPLA was replaced with artificial cerebrospinal fluid (aCSF). Suppression of nNOS by i.c.v. NPLA significantly reduced mean (+/- SE) spontaneous fetal swallowing (1.35 +/- 0.12 to 0.50 +/- 0.07 swallows/min; P < 0.001). Injection of ANG II in the presence of NPLA had no dipsogenic effect on fetal swallowing (0.68 +/- 0.09 swallows/min). In the aCSF study, i.c.v. aCSF did not change fetal swallowing (0.93 +/- 0.10 vs. 0.95 +/- 0.09 swallows/min), whereas i.c.v. ANG II resulted in a significant increase in the rate of fetal swallowing (2.0 +/- 0.04 swallows/min; P = 0.001). We speculate that the suppressive dipsogenic effects of central NPLA indicate that spontaneous and ANG II- stimulated fetal swallowing is dependent on central nNOS activity.
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Affiliation(s)
- Mostafa A El-Haddad
- Perinatal Research Laboratories, Harbor/University of California at Los Angeles Medical Center, University of California at Los Angeles School of Medicine, Torrance, California 90902, USA.
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Stern JE, Ludwig M. NO inhibits supraoptic oxytocin and vasopressin neurons via activation of GABAergic synaptic inputs. Am J Physiol Regul Integr Comp Physiol 2001; 280:R1815-22. [PMID: 11353687 DOI: 10.1152/ajpregu.2001.280.6.r1815] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To study modulatory actions of nitric oxide (NO) on GABAergic synaptic activity in hypothalamic magnocellular neurons in the supraoptic nucleus (SON), in vitro and in vivo electrophysiological recordings were obtained from identified oxytocin and vasopressin neurons. Whole cell patch-clamp recordings were obtained in vitro from immunochemically identified oxytocin and vasopressin neurons. GABAergic synaptic activity was assessed in vitro by measuring GABA(A) miniature inhibitory postsynaptic currents (mIPSCs). The NO donor and precursor sodium nitroprusside (SNP) and L-arginine, respectively, increased the frequency and amplitude of GABA(A) mIPSCs in both cell types (P < or = 0.001). Retrodialysis of SNP (50 mM) onto the SON in vivo inhibited the activity of both neuronal types (P < or = 0.002), an effect that was reduced by retrodialysis of the GABA(A)-receptor antagonist bicuculline (2 mM, P < or = 0.001). Neurons activated by intravenous infusion of 2 M NaCl were still strongly inhibited by SNP. These results suggest that NO inhibition of neuronal excitability in oxytocin and vasopressin neurons involves pre- and postsynaptic potentiation of GABAergic synaptic activity in the SON.
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Affiliation(s)
- J E Stern
- Department of Pharmacology and Toxicology, Wright State University, Dayton, Ohio 45435, USA.
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Nitric oxide stimulates ACTH secretion and the transcription of the genes encoding for NGFI-B, corticotropin-releasing factor, corticotropin-releasing factor receptor type 1, and vasopressin in the hypothalamus of the intact rat. J Neurosci 1999. [PMID: 10460269 DOI: 10.1523/jneurosci.19-17-07640.1999] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
We investigated the effect of the intracerebroventricular injection of the nitric oxide (NO) donor 3-morpholino-sydnonimine (SIN-1) on the release of adrenocorticotropin hormone (ACTH) and the neuronal response of hypothalamic neurons responsible for this release. Rats that were administered SIN-1 showed significant elevations in plasma ACTH levels, a response that was virtually abolished by antibodies against corticotropin-releasing factor (CRF) and significantly blunted by vasopressin (VP) antiserum. SIN-1 also upregulated heteronuclear (hn) transcripts for CRF and VP and messenger RNA (mRNA) levels for the immediate early gene NGFI-B and for CRF receptor type 1 (CRF-R(1)) in the parvocellular portion of the paraventricular nucleus (PVN) of the hypothalamus. Blockade of prostaglandin synthesis with ibuprofen did not alter the ACTH or the PVN response to SIN-1. The central nucleus of the amygdala and the supraoptic nucleus, regions that are involved in autonomic adjustments to altered cardiovascular activity, also responded to SIN-1 with elevated NGFI-B mRNA levels. However, the only change in mean arterial blood pressure caused by this NO donor was a transient and modest increase. To our knowledge, this is the first demonstration that in the intact rat NO stimulates the activity of PVN neurons that control the hypothalamic-pituitary-adrenal axis. It must be noted, however, that our results do not allow us to determine whether this effect was direct or mediated through PVN afferents. This study should help resolve the controversy generated by the use of isolated brain tissues to investigate the net effect of NO on hypothalamic peptide production.
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Popeski N, Amir S, Woodside B. Changes in NADPH-d staining in the paraventricular and supraoptic nuclei during pregnancy and lactation in rats: role of ovarian steroids and oxytocin. J Neuroendocrinol 1999; 11:53-61. [PMID: 9918229 DOI: 10.1046/j.1365-2826.1999.00291.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Staining for nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d), a histochemical marker for nitric oxide synthase (NOS), is increased in the supraoptic (SON) and paraventricular (PVN) nuclei in late pregnant rats. To determine whether increases in staining were evident at other times during pregnancy and lactation the number of cells that stained for NADPH-d in the SON and PVN in rats on days 4, 12, 16, and 22 of pregnancy and on days 4, 12, and 20 of lactation was compared to that in virgin females. In a second experiment the influence of ovarian hormones on NADPH-d staining was assessed by comparing staining in the SON and PVN among ovariectomized animals exposed to either a steroid hormone replacement schedule that mimics late pregnancy (oestrogen and progesterone with progesterone removal), oestrogen alone, oestrogen and progesterone, or cholesterol alone. In the last experiment of this series staining was compared among ovariectomized animals given either oestrogen or cholesterol priming accompanied by oxytocin (OT) or vehicle infusion into the third ventricle for 7 days. The number of cells showing dense staining for NADPH-d in both the SON and PVN increased on days 12 and 22 of pregnancy and 4 and 12 of lactation compared to that observed in virgins. NADPH-d staining in these areas was also increased by both the steroid treatment that mimicked late pregnancy and chronic central OT infusion in oestrogen-primed animals. These data suggest that NADPH-d staining in the SON and PVN is increased at times when oxytocinergic cells are known to be active and that the hormonal state associated with late pregnancy is sufficient to increase NADPH-d staining.
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Affiliation(s)
- N Popeski
- Centre for Studies in Behavioural Neurobiology, Psychology Department, Concordia University, Montréal, Québec, Canada
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