1
|
Shibao CA, Harrison DG, Biaggioni I. David Herlie Robertson, MD. Hypertension 2024; 81:e44-e46. [PMID: 38630798 DOI: 10.1161/hypertensionaha.124.22755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2024]
Affiliation(s)
- Cyndya A Shibao
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - David G Harrison
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Italo Biaggioni
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| |
Collapse
|
2
|
Biaggioni I, Arnold AC, Black B, Diedrich A, Furlan R, Gamboa A, Garland E, Jacob G, Jordan J, Okamoto LE, Raj SR, Sato K, Shannon J, Tank J, Peltier A, Shibao CA. In memoriam: a celebration of the autonomic contributions of David Robertson (1947-2024). Clin Auton Res 2024; 34:5-7. [PMID: 38436914 DOI: 10.1007/s10286-024-01025-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 01/25/2024] [Indexed: 03/05/2024]
Affiliation(s)
- Italo Biaggioni
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, 37232, USA.
| | - Amy C Arnold
- Department of Neural and Behavioral Sciences, Pennsylvania State University College of Medicine, Hershey, PA, USA
| | - Bonnie Black
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Andre Diedrich
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Raffaello Furlan
- Internal Medicine and Syncope Unit, Humanitas Research Hospital, Humanitas University, Rozzano, Italy
| | - Alfredo Gamboa
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Emily Garland
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Giris Jacob
- Deparment of Internal Medicine, Recanati Autonomic Dysfunction Center, Sourasky Medical Center and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Jens Jordan
- Institute of Aerospace Medicine, German Aerospace Center and Medical Faculty, University of Cologne, Cologne, Germany
| | - Luis E Okamoto
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Satish R Raj
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
- Department of Cardiac Sciences, Cumming School of Medicine, Libin Cardiovascular Institute, University of Calgary, Calgary, Canada
| | - Kyoko Sato
- Adachi Medical Center, Tokyo Women's Medical University, Tokyo, Japan
| | | | - Jens Tank
- Institute of Aerospace Medicine, German Aerospace Center and Medical Faculty, University of Cologne, Cologne, Germany
| | - Amanda Peltier
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Cyndya A Shibao
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| |
Collapse
|
3
|
Wassenberg T, Deinum J, van Ittersum FJ, Kamsteeg E, Pennings M, Verbeek MM, Wevers RA, van Albada ME, Kema IP, Versmissen J, van den Meiracker T, Lenders JW, Monnens L, Willemsen MA. Clinical presentation and long-term follow-up of dopamine beta hydroxylase deficiency. J Inherit Metab Dis 2021; 44:554-565. [PMID: 33034372 PMCID: PMC8246878 DOI: 10.1002/jimd.12321] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 09/26/2020] [Accepted: 10/05/2020] [Indexed: 12/23/2022]
Abstract
Dopamine beta hydroxylase (DBH) deficiency is an extremely rare autosomal recessive disorder with severe orthostatic hypotension, that can be treated with L-threo-3,4-dihydroxyphenylserine (L-DOPS). We aimed to summarize clinical, biochemical, and genetic data of all world-wide reported patients with DBH-deficiency, and to present detailed new data on long-term follow-up of a relatively large Dutch cohort. We retrospectively describe 10 patients from a Dutch cohort and 15 additional patients from the literature. We identified 25 patients (15 females) from 20 families. Ten patients were diagnosed in the Netherlands. Duration of follow-up of Dutch patients ranged from 1 to 21 years (median 13 years). All patients had severe orthostatic hypotension. Severely decreased or absent (nor)epinephrine, and increased dopamine plasma concentrations were found in 24/25 patients. Impaired kidney function and anemia were present in all Dutch patients, hypomagnesaemia in 5 out of 10. Clinically, all patients responded very well to L-DOPS, with marked reduction of orthostatic complaints. However, orthostatic hypotension remained present, and kidney function, anemia, and hypomagnesaemia only partially improved. Plasma norepinephrine increased and became detectable, while epinephrine remained undetectable in most patients. We confirm the core clinical characteristics of DBH-deficiency and the pathognomonic profile of catecholamines in body fluids. Impaired renal function, anemia, and hypomagnesaemia can be part of the clinical presentation. The subjective response to L-DOPS treatment is excellent and sustained, although the neurotransmitter profile in plasma does not normalize completely. Furthermore, orthostatic hypotension as well as renal function, anemia, and hypomagnesaemia improve only partially.
Collapse
Affiliation(s)
- Tessa Wassenberg
- Department of Neurology, Donders Institute for Brain, Cognition and BehaviourRadboud University Medical CenterNijmegenthe Netherlands
- Department of Pediatrics, Pediatric Neurology UnitUZ Brussel VUBBrusselsBelgium
| | - Jaap Deinum
- Department of Internal MedicineRadboud University Medical CenterNijmegenthe Netherlands
| | - Frans J. van Ittersum
- Department of NephrologyAmsterdam University Medical Center (location VUMC)Amsterdamthe Netherlands
| | - Erik‐Jan Kamsteeg
- Department of Human GeneticsRadboud University Medical CenterNijmegenthe Netherlands
| | - Maartje Pennings
- Department of Human GeneticsRadboud University Medical CenterNijmegenthe Netherlands
| | - Marcel M. Verbeek
- Department of Neurology, Donders Institute for Brain, Cognition and BehaviourRadboud University Medical CenterNijmegenthe Netherlands
- Department of Laboratory Medicine, Translational Metabolic LaboratoryRadboud University Medical CenterNijmegenthe Netherlands
| | - Ron A. Wevers
- Department of Laboratory Medicine, Translational Metabolic LaboratoryRadboud University Medical CenterNijmegenthe Netherlands
| | - Mirjam E. van Albada
- Department of PediatricsUniversity Medical Center GroningenGroningenthe Netherlands
| | - Ido P. Kema
- Department of Laboratory MedicineUniversity Medical Center Groningen, University of GroningenGroningenthe Netherlands
| | - Jorie Versmissen
- Department of Internal MedicineErasmus Medical CenterRotterdamthe Netherlands
| | | | - Jacques W.M. Lenders
- Department of Internal MedicineRadboud University Medical CenterNijmegenthe Netherlands
- Department of Medicine III, University Hospital Carl Gustav CarusTechnical University DresdenDresdenGermany
| | - Leo Monnens
- Department of PhysiologyRadboud University Medical CenterNijmegenthe Netherlands
| | - Michèl A. Willemsen
- Department of Pediatric Neurology, Donders Institute for Brain, Cognition and Behaviour, Amalia Children's HospitalRadboud University Medical CenterNijmegenthe Netherlands
| |
Collapse
|
4
|
Gonzalez‐Lopez E, Vrana KE. Dopamine beta‐hydroxylase and its genetic variants in human health and disease. J Neurochem 2019; 152:157-181. [DOI: 10.1111/jnc.14893] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 09/18/2019] [Accepted: 09/26/2019] [Indexed: 12/12/2022]
Affiliation(s)
| | - Kent E. Vrana
- Department of Pharmacology Penn State College of Medicine Hershey PA USA
| |
Collapse
|
5
|
FoxO1 in dopaminergic neurons regulates energy homeostasis and targets tyrosine hydroxylase. Nat Commun 2016; 7:12733. [PMID: 27681312 PMCID: PMC5056402 DOI: 10.1038/ncomms12733] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Accepted: 07/28/2016] [Indexed: 01/05/2023] Open
Abstract
Dopaminergic (DA) neurons are involved in the integration of neuronal and hormonal signals to regulate food consumption and energy balance. Forkhead transcriptional factor O1 (FoxO1) in the hypothalamus plays a crucial role in mediation of leptin and insulin function. However, the homoeostatic role of FoxO1 in DA system has not been investigated. Here we report that FoxO1 is highly expressed in DA neurons and mice lacking FoxO1 specifically in the DA neurons (FoxO1 KODAT) show markedly increased energy expenditure and interscapular brown adipose tissue (iBAT) thermogenesis accompanied by reduced fat mass and improved glucose/insulin homoeostasis. Moreover, FoxO1 KODAT mice exhibit an increased sucrose preference in concomitance with higher dopamine and norepinephrine levels. Finally, we found that FoxO1 directly targets and negatively regulates tyrosine hydroxylase (TH) expression, the rate-limiting enzyme of the catecholamine synthesis, delineating a mechanism for the KO phenotypes. Collectively, these results suggest that FoxO1 in DA neurons is an important transcriptional factor that directs the coordinated control of energy balance, thermogenesis and glucose homoeostasis. Dopaminergic neurons are important for regulating energy homeostasis. Here, the authors show the transcription factor FoxO1 negatively regulates tyrosine hydroxylase expression in midbrain dopaminergic neurons, and plays an important role in regulation of glucose homeostasis, energy expenditure, and resistance to diet-induced obesity.
Collapse
|
6
|
Verberne AJM, Korim WS, Sabetghadam A, Llewellyn-Smith IJ. Adrenaline: insights into its metabolic roles in hypoglycaemia and diabetes. Br J Pharmacol 2016; 173:1425-37. [PMID: 26896587 DOI: 10.1111/bph.13458] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 01/20/2016] [Accepted: 02/11/2016] [Indexed: 01/05/2023] Open
Abstract
Adrenaline is a hormone that has profound actions on the cardiovascular system and is also a mediator of the fight-or-flight response. Adrenaline is now increasingly recognized as an important metabolic hormone that helps mobilize energy stores in the form of glucose and free fatty acids in preparation for physical activity or for recovery from hypoglycaemia. Recovery from hypoglycaemia is termed counter-regulation and involves the suppression of endogenous insulin secretion, activation of glucagon secretion from pancreatic α-cells and activation of adrenaline secretion. Secretion of adrenaline is controlled by presympathetic neurons in the rostroventrolateral medulla, which are, in turn, under the control of central and/or peripheral glucose-sensing neurons. Adrenaline is particularly important for counter-regulation in individuals with type 1 (insulin-dependent) diabetes because these patients do not produce endogenous insulin and also lose their ability to secrete glucagon soon after diagnosis. Type 1 diabetic patients are therefore critically dependent on adrenaline for restoration of normoglycaemia and attenuation or loss of this response in the hypoglycaemia unawareness condition can have serious, sometimes fatal, consequences. Understanding the neural control of hypoglycaemia-induced adrenaline secretion is likely to identify new therapeutic targets for treating this potentially life-threatening condition.
Collapse
Affiliation(s)
- A J M Verberne
- Clinical Pharmacology and Therapeutics Unit, Department of Medicine, Austin Health, University of Melbourne, Heidelberg, VIC, Australia
| | - W S Korim
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - A Sabetghadam
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - I J Llewellyn-Smith
- Cardiovascular Medicine and Human Physiology, Flinders University, Bedford Park, SA, Australia
| |
Collapse
|
7
|
Groothuis JT, Thijssen DHJ, Lenders JWM, Deinum J, Hopman MTE. Leg vasoconstriction during head-up tilt in patients with autonomic failure is not abolished. J Appl Physiol (1985) 2011; 110:416-22. [PMID: 21127209 DOI: 10.1152/japplphysiol.01098.2010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Maintaining blood pressure during orthostatic challenges is primarily achieved by baroreceptor-mediated activation of the sympathetic nervous system, which can be divided into preganglionic and postganglionic parts. Despite their preganglionic autonomic failure, spinal cord-injured individuals demonstrate a preserved peripheral vasoconstriction during orthostatic challenges. Whether this also applies to patients with postganglionic autonomic failure is unknown. Therefore, we assessed leg vasoconstriction during 60° head-up tilt in five patients with pure autonomic failure (PAF) and two patients with autonomic failure due to dopamine-β-hydroxylase (DBH) deficiency. Ten healthy subjects served as controls. Leg blood flow was measured using duplex ultrasound in the right superficial femoral artery. Leg vascular resistance was calculated as the arterial-venous pressure gradient divided by blood flow. DBH-deficient patients were tested off and on the norepinephrine pro-drug l-threo-dihydroxyphenylserine (l-DOPS). During 60° head-up tilt, leg vascular resistance increased significantly in PAF patients [0.40 ± 0.38 (+30%) mmHg·ml−1·min−1]. The increase in leg vascular resistance was not significantly different from controls [0.88 ± 1.04 (+72%) mmHg·ml−1·min−1]. In DBH-deficient patients, leg vascular resistance increased by 0.49 ± 0.01 (+153%) and 1.52 ± 1.47 (+234%) mmHg·ml−1·min−1 off and on l-DOPS, respectively. Despite the increase in leg vascular resistance, orthostatic hypotension was present in PAF and DBH-deficient patients. Our results demonstrate that leg vasoconstriction during orthostatic challenges in patients with PAF or DBH deficiency is not abolished. This indicates that the sympathetic nervous system is not the sole or pivotal mechanism inducing leg vasoconstriction during orthostatic challenges. Additional vasoconstrictor mechanisms may compensate for the loss in sympathetic nervous system control.
Collapse
Affiliation(s)
- Jan T. Groothuis
- Departments of 1Physiology and
- Department of Rehabilitation, Sint Maartenskliniek, Nijmegen, The Netherlands
| | - Dick H. J. Thijssen
- Departments of 1Physiology and
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom; and
| | - Jacques W. M. Lenders
- Internal Medicine, Radboud University Nijmegen Medical Centre, Nijmegen
- Department of Medicine III, Carl Gustav Carus University Medical Center, Dresden, Germany
| | - Jaap Deinum
- Internal Medicine, Radboud University Nijmegen Medical Centre, Nijmegen
| | | |
Collapse
|
8
|
Wallin BG, Charkoudian N. Sympathetic neural control of integrated cardiovascular function: Insights from measurement of human sympathetic nerve activity. Muscle Nerve 2007; 36:595-614. [PMID: 17623856 DOI: 10.1002/mus.20831] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Sympathetic neural control of cardiovascular function is essential for normal regulation of blood pressure and tissue perfusion. In the present review we discuss sympathetic neural mechanisms in human cardiovascular physiology and pathophysiology, with a focus on evidence from direct recordings of sympathetic nerve activity using microneurography. Measurements of sympathetic nerve activity to skeletal muscle have provided extensive information regarding reflex control of blood pressure and blood flow in conditions ranging from rest to postural changes, exercise, and mental stress in populations ranging from healthy controls to patients with hypertension and heart failure. Measurements of skin sympathetic nerve activity have also provided important insights into neural control, but are often more difficult to interpret since the activity contains several types of nerve impulses with different functions. Although most studies have focused on group mean differences, we provide evidence that individual variability in sympathetic nerve activity is important to the ultimate understanding of these integrated physiological mechanisms.
Collapse
Affiliation(s)
- B Gunnar Wallin
- Institute of Neuroscience and Physiology, Sahlgrenska Academy at Göteborg University, S-413 45 Göteborg, Sweden.
| | | |
Collapse
|
9
|
Cogliati C, Colombo S, Ruscone TG, Gruosso D, Porta A, Montano N, Malliani A, Furlan R. Acute β-Blockade Increases Muscle Sympathetic Activity and Modifies Its Frequency Distribution. Circulation 2004; 110:2786-91. [PMID: 15505096 DOI: 10.1161/01.cir.0000146335.69413.f9] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
The possible mechanisms by which β-adrenergic antagonists may act on the neural regulation of the cardiovascular system are still elusive. Recent studies reported a marked increase of postganglionic muscle sympathetic nerve activity (MSNA) after acute β-blockade associated with unchanged values of arterial blood pressure and baroreflex sensitivity. We tested the hypothesis that acute β-blockade might also alter the oscillatory characteristics of MSNA, thus decreasing its effectiveness on peripheral vasoconstriction.
Methods and Results—
In 11 healthy volunteers, ECG, MSNA, arterial pressure, and respiration were recorded before and after atenolol (0.05 mg/kg IV bolus) administration. The frequency distribution of RR interval, MSNA, systolic arterial pressure (SAP), and respiratory variability was assessed by spectrum and cross-spectrum analysis. Spontaneous baroreflex sensitivity (α-index) and plasma catecholamines (high-performance liquid chromatography) were measured. Atenolol induced a significant increase in RR interval (14.3±1.6%) with no changes in systolic and diastolic arterial pressure. MSNA increased (42±13% from 18±2 bursts per minute). The low-frequency (LF) component of RR and MSNA variability decreased (−44±7% and −24±5%, respectively), whereas the high-frequency (HF) component increased (163±55% and 34±11%, respectively), expressed in normalized units. Spectral coherence, an index of oscillatory coupling, decreased between LF
RR
and LF
MSNA
, whereas it increased between HF
MSNA
and HF
Resp
. SAP variability, α-index, and plasma catecholamines remained unchanged.
Conclusions—
Atenolol induced a change in MSNA frequency distribution reflecting a stronger respiratory coupling. This shift toward high frequency, despite an increase in MSNA, may lead to a less efficient sympathetic vasomotor modulation.
Collapse
|
10
|
Furlan R, Porta A, Costa F, Tank J, Baker L, Schiavi R, Robertson D, Malliani A, Mosqueda-Garcia R. Oscillatory patterns in sympathetic neural discharge and cardiovascular variables during orthostatic stimulus. Circulation 2000; 101:886-92. [PMID: 10694528 DOI: 10.1161/01.cir.101.8.886] [Citation(s) in RCA: 248] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND We tested the hypothesis that a common oscillatory pattern might characterize the rhythmic discharge of muscle sympathetic nerve activity (MSNA) and the spontaneous variability of heart rate and systolic arterial pressure (SAP) during a physiological increase of sympathetic activity induced by the head-up tilt maneuver. METHODS AND RESULTS Ten healthy subjects underwent continuous recordings of ECG, intra-arterial pressure, respiratory activity, central venous pressure, and MSNA, both in the recumbent position and during 75 degrees head-up tilt. Venous samplings for catecholamine assessment were obtained at rest and during the fifth minute of tilt. Spectrum and cross-spectrum analyses of R-R interval, SAP, and MSNA variabilities and of respiratory activity provided the low (LF, 0.1 Hz) and high frequency (HF, 0.27 Hz) rhythmic components of each signal and assessed their linear relationships. Compared with the recumbent position, tilt reduced central venous pressure, but blood pressure was unchanged. Heart rate, MSNA, and plasma epinephrine and norepinephrine levels increased, suggesting a marked enhancement of overall sympathetic activity. During tilt, LF(MSNA) increased compared with the level in the supine position; this mirrored similar changes observed in the LF components of R-R interval and SAP variabilities. The increase of LF(MSNA) was proportional to the amount of the sympathetic discharge. The coupling between LF components of MSNA and R-R interval and SAP variabilities was enhanced during tilt compared with rest. CONCLUSIONS During the sympathetic activation induced by tilt, a similar oscillatory pattern based on an increased LF rhythmicity characterized the spontaneous variability of neural sympathetic discharge, R-R interval, and arterial pressure.
Collapse
Affiliation(s)
- R Furlan
- Centro Ricerche Cardiovascolari, CNR, Medicina Interna II, Ospedale L. Sacco, and Centro LITA di Vialba, Università degli Studi di Milano, Milan, Italy.
| | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Furlan R, Jacob G, Snell M, Robertson D, Porta A, Harris P, Mosqueda-Garcia R. Chronic orthostatic intolerance: a disorder with discordant cardiac and vascular sympathetic control. Circulation 1998; 98:2154-9. [PMID: 9815870 DOI: 10.1161/01.cir.98.20.2154] [Citation(s) in RCA: 146] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Chronic orthostatic intolerance (COI) is a debilitating autonomic condition in young adults. Its neurohumoral and hemodynamic profiles suggest possible alterations of postural sympathetic function and of baroreflex control of heart rate (HR). METHODS AND RESULTS In 16 COI patients and 16 healthy volunteers, intra-arterial blood pressure (BP), ECG, central venous pressure (CVP), and muscle sympathetic nerve activity (MSNA) were recorded at rest and during 75 degrees tilt. Spectral analysis of RR interval and systolic arterial pressure (SAP) variabilities provided indices of sympathovagal modulation of the sinoatrial node (ratio of low-frequency to high-frequency components, LF/HF) and of sympathetic vasomotor control (LFSAP). Baroreflex mechanisms were assessed (1) by the slope of the regression line obtained from changes of RR interval and MSNA evoked by pharmacologically induced alterations in BP and (2) by the index alpha, obtained from cross-spectral analysis of RR and SAP variabilities. At rest, HR, MSNA, LF/HF, and LFSAP were higher in COI patients, whereas BP and CVP were similar in the two groups. During tilt, BP did not change and CVP fell by the same extent in the 2 groups; the increase of HR and LF/HF was more pronounced in COI patients. Conversely, the increase of MSNA was lower in COI than in control subjects. Baroreflex sensitivity was similar in COI and control subjects at rest; tilt reduced alpha similarly in both groups. CONCLUSIONS COI is characterized by an overall enhancement of noradrenergic tone at rest and by a blunted postganglionic sympathetic response to standing, with a compensatory cardiac sympathetic overactivity. Baroreflex mechanisms maintain their functional responsiveness. These data suggest that in COI, the functional distribution of central sympathetic tone to the heart and vasculature is abnormal.
Collapse
Affiliation(s)
- R Furlan
- Syncope Service in the Autonomic Dysfunction Unit, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN, USA
| | | | | | | | | | | | | |
Collapse
|
12
|
Mosqueda-Garcia R, Fernandez-Violante R, Tank J, Snell M, Cunningham G, Furlan R. Yohimbine in neurally mediated syncope. Pathophysiological implications. J Clin Invest 1998; 102:1824-30. [PMID: 9819368 PMCID: PMC509132 DOI: 10.1172/jci3050] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
In this study, we evaluated if increased sympathetic stimulation is an essential requirement for the development of neurally mediated syncope (NMS) by manipulating overall sympathetic outflow in subjects susceptible to tilt-induced syncope. Eight previously characterized patients with recurrent NMS (five females and three males; 34+/-2 yr) were recruited from the Vanderbilt Syncope Unit and eight age-matched controls underwent initial administration of clonidine (CLO) or yohimbine (YHO). This was done, prospectively, to determine doses of these agents that would increase or decrease plasma norepinephrine levels by >/= 30%. On a different day, in all subjects we determined intraarterial blood pressure, EKG and muscle sympathetic nerve activity (MSNA) both supine and during upright tilt. After this, subjects randomly received either CLO or YHO, and 3 h later another tilt was performed. After 1 wk, a similar procedure with the other drug was performed. During the two basal tilts, all the control subjects completed the study, whereas all the NMS patients developed syncope. Reduction in sympathetic tone by CLO resulted in a decreased tolerance to tilt in three out of eight controls and in all the NMS patients. In contrast, YHO not only increased basal plasma NorEpi levels and MSNA, but also prevented syncope in seven out of eight patients. In a selected population of patients, increased sympathetic activity is not a prerequisite for the development of syncope. Yohimbine-induced enhancement of sympathetic tone in patients with NMS improves orthostatic tolerance and raises the possibility that this drug may be a useful agent in the treatment of NMS.
Collapse
Affiliation(s)
- R Mosqueda-Garcia
- The Syncope Service in the Autonomic Dysfunction Unit, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee 37232, USA
| | | | | | | | | | | |
Collapse
|
13
|
Smith GD, Watson LP, Mathias CJ. Differing haemodynamic and catecholamine responses to exercise in three groups with peripheralautonomic dysfunction: insulin-dependent diabetes mellitus, familial amyloid polyneuropathy and pure autonomic failure. JOURNAL OF THE AUTONOMIC NERVOUS SYSTEM 1998; 73:125-34. [PMID: 9862387 DOI: 10.1016/s0165-1838(98)00132-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The haemodynamic and catecholamine responses to supine exercise, and the effect on standing blood pressure (BP), were studied in three groups with peripheral autonomic dysfunction; insulin-dependent diabetes mellitus (IDDM), familial amyloid polyneuropathy (FAP) and pure autonomic failure (PAF). Healthy normal subjects were studied as controls. With exercise, BP increased in controls, was unchanged in IDDM and FAP, and fell in PAF. Heart rate (HR) increased more in controls than IDDM, FAP or PAF. Cardiac index (CI) increased less in IDDM than controls, FAP or PAF. Systemic vascular resistance (SVR) fell similarly in controls and IDDM, with a greater fall in FAP and PAF. Plasma noradrenaline increased in controls and IDDM only; plasma adrenaline did not change and plasma dopamine was undetectable in all groups. On standing, BP was unchanged in controls; BP fell pre- and post-exercise in IDDM, FAP and PAF, with a significantly greater fall post-exercise in FAP and PAF. In conclusion, the haemodynamic responses to supine exercise and to standing after exercise differed in the three groups with peripheral autonomic dysfunction. These differences, and also the similarities, between different forms of peripheral autonomic dysfunction, may be of relevance to the clinical assessment and therapy of these patients.
Collapse
Affiliation(s)
- G D Smith
- Division of Neuroscience and Psychological Medicine, Imperial College School of Medicine, at St. Mary's Hospital, London, UK
| | | | | |
Collapse
|
14
|
Baliga RR, Catz AB, Watson LD, Short DJ, Frankel HL, Mathias CJ. Cardiovascular and hormonal responses to food ingestion in humans with spinal cord transection. Clin Auton Res 1997; 7:137-41. [PMID: 9232358 DOI: 10.1007/bf02308841] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In sympathetic denervation due to primary autonomic failure, ingestion of food causes a fall in blood pressure (BP) and exacerbates postural hypotension. It is not known whether these responses occur in tetraplegics with physiologically complete cervical spinal cord transection, who also have sympathetic dysfunction because of disruption of descending spinal sympathetic pathways. We, therefore, studied the effect of a liquid meal on BP, heart rate (HR) and neurohormonal levels in tetraplegics. Paraplegics with low lesions and without sympathetic dysfunction served as controls. After food ingestion, there was no fall in BP in tetraplegics or in controls. HR did not change in either group. After fund, plasma noradrenaline was unchanged in tetraplegics, but rose in controls, while plasma renin activity (PRA) rose in tetraplegics but not in controls. The fall in BP and rise in HR on head-up tilt after the meal in tetraplegics was similar to that before the meal. There was no change in PRA following pre-prandial tilt in either group; post-prandial tilt raised levels in the tetraplegics, unlike in controls. Thus there is considerable variance in the responses to food between tetraplegics and paraplegic controls, and even greater differences when compared with published data in other autonomic disorders with sympathetic dysfunction; this may relate to the site and the nature of the sympathetic lesion and the ability to activate compensatory mechanisms.
Collapse
Affiliation(s)
- R R Baliga
- Department of Medicine, St Mary's Hospital/Imperial College School of Medicine, University of London, UK.
| | | | | | | | | | | |
Collapse
|
15
|
Mosqueda-Garcia R, Furlan R, Fernandez-Violante R, Desai T, Snell M, Jarai Z, Ananthram V, Robertson RM, Robertson D. Sympathetic and baroreceptor reflex function in neurally mediated syncope evoked by tilt. J Clin Invest 1997; 99:2736-44. [PMID: 9169504 PMCID: PMC508120 DOI: 10.1172/jci119463] [Citation(s) in RCA: 190] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The pathophysiology of neurally mediated syncope is poorly understood. It has been widely assumed that excessive sympathetic activation in a setting of left ventricular hypovolemia stimulates ventricular afferents that trigger hypotension and bradycardia. We tested this hypothesis by determining if excessive sympathetic activation precedes development of neurally mediated syncope, and if this correlates with alterations in baroreflex function. We studied the changes in intraarterial blood pressure (BP), heart rate (HR), central venous pressure (CVP), muscle sympathetic nerve activity (MSNA), and plasma catecholamines evoked by upright tilt in recurrent neurally mediated syncope patients (SYN, 5+/-1 episodes/mo, n = 14), age- and sex-matched controls (CON, n = 23), and in healthy subjects who consistently experienced syncope during tilt (FS+, n = 20). Baroreflex responses were evaluated from changes in HR, BP, and MSNA that were obtained after infusions of phenylephrine and sodium nitroprusside. Compared to CON, patients with SYN had blunted increases in MSNA at low tilt levels, followed by a progressive decrease and ultimately complete disappearance of MSNA with syncope. SYN patients also had attenuation of norepinephrine increases and lower baroreflex slope sensitivity, both during tilt and after pharmacologic testing. FS+ subjects had the largest decrease in CVP with tilt and had significant increases in MSNA and heart rate baroreflex slopes. These data challenge the view that excessive generalized sympathetic activation is the precursor of the hemodynamic abnormality underlying recurrent neurally mediated syncope.
Collapse
Affiliation(s)
- R Mosqueda-Garcia
- Syncope Service in the Autonomic Dysfunction Unit, Vanderbilt University Medical Center, Nashville, Tennessee 37232-2195, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Carvalho MJ, van den Meiracker AH, Boomsma F, Man in 't Veld AJ, Freitas J, Costa O, de Freitas AF. Improved orthostatic tolerance in familial amyloidotic polyneuropathy with unnatural noradrenaline precursor L-threo-3,4-dihydroxyphenylserine. JOURNAL OF THE AUTONOMIC NERVOUS SYSTEM 1997; 62:63-71. [PMID: 9021651 DOI: 10.1016/s0165-1838(96)00110-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Disabling orthostatic hypotension, due to insufficiency of the autonomic nervous system, is a common complication of type I familial amyloidotic polyneuropathy (FAP). We investigated whether oral treatment with L-threo-3,4-dihydroxyphenylserine (L-threo-Dops), a noradrenaline precursor, might be of therapeutical benefit. In twenty untreated FAP patients, aged 33 to 44 years, who, because of severe orthostatic hypotension, were bedridden or constrained to a sitting life, supine and erect blood pressure (BP), plasma noradrenaline and tilting time, defined as the interval (s) between the beginning of a 60 degrees head-up tilt and the occurrence of orthostatic symptoms (dizziness, blurred vision or near syncope) were determined before and at repeated intervals during oral treatment with L-threo-Dops, 100 mg bid, for 6 months. Before treatment supine mean BP was 80 (76-85) mmHg (mean and 95% CI), supine plasma noradrenaline was low, 59 (41-77) pg/ml and tilting time ranged from 38 to 118 s. In response to tilt, mean BP immediately fell by 36 (31-41) mmHg, whereas plasma noradrenaline increased by only 11 (0-21) pg/ml (p = 0.05). After 3 to 5 days of treatment with L-threo-Dops all patients experienced marked improvement of their orthostatic tolerance as reflected by their ability to walk freely around. This effect sustained throughout the six months of treatment. Plasma noradrenaline increased moderately by 37 (11-63) pg/ml (p = 0.02) and supine mean BP increased by 8.6 (5.8-12.4) mmHg (p < 0.001) during chronic treatment. Supine or nocturnal hypertension did not develop, the fall in mean BP in response to tilt diminished by 12.5 (6.5-17.3) mmHg (p < 0.001) and tilting time became longer than 600 s in all patients. Because of its efficacy, its sustained duration of action and the lack of side effects, L-threo-Dops is advocated to improve orthostatic tolerance in patients with autonomic insufficiency due to FAP.
Collapse
Affiliation(s)
- M J Carvalho
- Centro de Estudos de Funçao Autonomica Hospital S. Joao, Oporto, Portugal
| | | | | | | | | | | | | |
Collapse
|
17
|
Thompson JM, O'Callaghan CJ, Kingwell BA, Lambert GW, Jennings GL, Esler MD. Total norepinephrine spillover, muscle sympathetic nerve activity and heart-rate spectral analysis in a patient with dopamine beta-hydroxylase deficiency. JOURNAL OF THE AUTONOMIC NERVOUS SYSTEM 1995; 55:198-206. [PMID: 8801271 DOI: 10.1016/0165-1838(95)00048-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Dopamine-beta-hydroxylase (D beta H) is the enzyme responsible for intraneural conversion of dopamine to norepinephrine. Its deficiency results in failure of norepinephrine synthesis, excessive dopamine release and orthostatic hypotension. We studied a young patient with this deficiency using the currently available methods to assess sympathetic function namely measurement of norepinephrine kinetics, microneurography to assess muscle sympathetic nerve activity (MSNA), and heart-rate spectral analysis. We compared these findings with those in 24 young healthy controls, and 4 patients with peripheral autonomic failure (PAF). Recordings were made in our subject before and after 5 months of treatment with L-threo-3,4-dihydroxyphenylserine (DOPS) (which is converted directly into L-norepinephrine bypassing the D beta H enzymatic step); measurements were made at rest in the supine position and after 15 min of 30 degrees head-up tilt. Our subject with D beta H deficiency had a high resting nerve firing rate (40.3 bursts/min) compared with the mean value in normal controls (19.3 bursts/min), and an appropriate increase in nerve firing rate during tilt. Total body norepinephrine spillover at rest was very low, 38 ng/min, compared with age-matched normals (519 +/- 43.3 ng/min, mean +/- SEM), and epinephrine secretion was undetectable. Conversely, the plasma concentrations of dopamine, DOPAC, HVA and DOPA were raised. At rest, low-frequency heart-rate variability (0.1 Hz) was absent with preservation of the respiratory-related high-frequency peak. In contrast, the PAF subjects had no detectable muscle sympathetic nerve activity, very low levels of norepinephrine spillover and epinephrine secretion and a reduction in heart rate variability at all frequencies. After 5 months treatment with L-threo-3,4-dihydroxyphenylserine (DOPS) in the D beta H deficiency patient there was a dramatic clinical improvement with resolution of the orthostatic symptoms, dramatic reduction in MSNA activity at rest, and return of plasma norepinephrine, norepinephrine spillover, DHPG and MHPG to within the normal range, indicating intraneuronal production of norepinephrine.
Collapse
Affiliation(s)
- J M Thompson
- Alfred Baker Medical Unit, Alfred Hospital, Victoria, Australia
| | | | | | | | | | | |
Collapse
|
18
|
Robertson D, Haile V, Perry SE, Robertson RM, Phillips JA, Biaggioni I. Dopamine beta-hydroxylase deficiency. A genetic disorder of cardiovascular regulation. Hypertension 1991; 18:1-8. [PMID: 1677640 DOI: 10.1161/01.hyp.18.1.1] [Citation(s) in RCA: 106] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Dopamine beta-hydroxylase (DBH) deficiency is a genetic disorder in which affected patients cannot synthesize norepinephrine, epinephrine, and octopamine in either the central nervous system or the peripheral autonomic neurons. Dopamine acts as a false neurotransmitter in their noradrenergic neurons. Neonates with DBH deficiency have had episodic hypothermia, hypoglycemia, and hypotension, but survivors sometimes cope relatively well until late childhood when overwhelming orthostatic hypotension profoundly limits their activities. The hypotension may be so severe that clonic seizures supervene. Most currently recognized patients are young or middle-aged adults. The diagnosis is established by the observation of severe orthostatic hypotension in a patient whose plasma norepinephrine/dopamine ratio is much less than one.
Collapse
Affiliation(s)
- D Robertson
- Department of Pharmacology, Vanderbilt University, Nashville, Tenn. 37232-2195
| | | | | | | | | | | |
Collapse
|
19
|
Biaggioni I, Killian TJ, Mosqueda-Garcia R, Robertson RM, Robertson D. Adenosine increases sympathetic nerve traffic in humans. Circulation 1991; 83:1668-75. [PMID: 2022024 DOI: 10.1161/01.cir.83.5.1668] [Citation(s) in RCA: 140] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND Adenosine is an effective hypotensive agent in experimental animals and in anesthetized patients, producing little if any evidence of reflex sympathetic activation. In contrast, adenosine increases systolic blood pressure and heart rate in conscious subjects. To determine whether this response is related to sympathetic activation, we studied the cardiovascular and respiratory effects of adenosine in normal subjects while measuring muscle sympathetic nerve traffic through direct recordings from a peroneal nerve. METHODS AND RESULTS Adenosine (80 micrograms/kg/min i.v.) increased heart rate (+32 +/- 3 beats/min), systolic blood pressure (+10 +/- 2 mm Hg), and minute ventilation (+7 +/- 1 l/min). This was accompanied by a dose-dependent increase in muscle sympathetic nerve activity (from 198 +/- 52 to 451 +/- 92 units/min). Adenosine also produced a small, but consistent, decrease in diastolic blood pressure (-6 +/- 3 mm Hg). Adenosine produced a greater increase in sympathetic nerve traffic (145 +/- 32% above baseline) than did nitroprusside (65 +/- 16%) at doses that resulted in equivalent decreased in diastolic blood pressure. Arterial baroreceptor unloading, therefore, could not totally explain the increase in sympathetic traffic produced by adenosine. CONCLUSIONS Given the constellation of findings of increased ventilation and sympathetic activity, we, therefore, propose that adenosine increases sympathetic tone by activating afferent nerves, including arterial chemoreceptors. Contrary to the known inhibitory actions of adenosine on central and peripheral efferent systems, this and other reports suggest that adenosine-induced activation of afferent nerves, leading to sympathetic activation, may be a more widespread phenomenon than previously recognized.
Collapse
Affiliation(s)
- I Biaggioni
- Department of Medicine, Vanderbilt University, Nashville, TN 37232-2195
| | | | | | | | | |
Collapse
|