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Murphy M, Lee A, Willard F, Price K. Bilateral paramedian thalamic infarction in the setting of uncontrolled atrial fibrillation with rapid ventricular response. BMJ Case Rep 2024; 17:e260687. [PMID: 39256171 DOI: 10.1136/bcr-2024-260687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/12/2024] Open
Abstract
This case report outlines the first reported case of bilateral paramedian thalamic infarct, likely stemming from a rare artery of Percheron (AOP) variant, secondary to uncontrolled atrial fibrillation with rapid ventricular response. We underscore the importance of considering hypoperfusion due to decreased cerebral perfusion as a potential mechanism in cryptogenic AOP infarcts, challenging the conventional association with embolic etiology. This report contributes to the limited literature on AOP infarctions, emphasizing the need for heightened awareness among healthcare providers for diverse clinical presentations and potential etiologies to improve diagnosis and management, ultimately enhancing patient outcomes.
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Affiliation(s)
- Melissa Murphy
- Osteopathic Medicine, University of New England College, Biddeford, Maine, USA
| | - Andrew Lee
- Manchester Memorial Hospital, Manchester, Connecticut, USA
| | - Frank Willard
- Osteopathic Medicine, University of New England College, Biddeford, Maine, USA
| | - Kevin Price
- Manchester Memorial Hospital, Manchester, Connecticut, USA
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2
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Dammavalam V, Lin S, Nessa S, Daksla N, Stefanowski K, Costa A, Bergese S. Neuroprotection during Thrombectomy for Acute Ischemic Stroke: A Review of Future Therapies. Int J Mol Sci 2024; 25:891. [PMID: 38255965 PMCID: PMC10815099 DOI: 10.3390/ijms25020891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 01/08/2024] [Accepted: 01/09/2024] [Indexed: 01/24/2024] Open
Abstract
Stroke is a major cause of death and disability worldwide. Endovascular thrombectomy has been impactful in decreasing mortality. However, many clinical results continue to show suboptimal functional outcomes despite high recanalization rates. This gap in recanalization and symptomatic improvement suggests a need for adjunctive therapies in post-thrombectomy care. With greater insight into ischemia-reperfusion injury, recent preclinical testing of neuroprotective agents has shifted towards preventing oxidative stress through upregulation of antioxidants and downstream effectors, with positive results. Advances in multiple neuroprotective therapies, including uric acid, activated protein C, nerinetide, otaplimastat, imatinib, verapamil, butylphthalide, edaravone, nelonemdaz, ApTOLL, regional hypothermia, remote ischemic conditioning, normobaric oxygen, and especially nuclear factor erythroid 2-related factor 2, have promising evidence for improving stroke care. Sedation and blood pressure management in endovascular thrombectomy also play crucial roles in improved stroke outcomes. A hand-in-hand approach with both endovascular therapy and neuroprotection may be the key to targeting disability due to stroke.
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Affiliation(s)
- Vikalpa Dammavalam
- Department of Neurology, Stony Brook University Hospital, Stony Brook, NY 11794, USA; (V.D.); (K.S.)
| | - Sandra Lin
- Department of Anesthesiology, Stony Brook University Hospital, Stony Brook, NY 11794, USA; (S.L.); (N.D.); (A.C.)
| | - Sayedatun Nessa
- Department of Neurology, Stony Brook University Hospital, Stony Brook, NY 11794, USA; (V.D.); (K.S.)
| | - Neil Daksla
- Department of Anesthesiology, Stony Brook University Hospital, Stony Brook, NY 11794, USA; (S.L.); (N.D.); (A.C.)
| | - Kamil Stefanowski
- Department of Neurology, Stony Brook University Hospital, Stony Brook, NY 11794, USA; (V.D.); (K.S.)
| | - Ana Costa
- Department of Anesthesiology, Stony Brook University Hospital, Stony Brook, NY 11794, USA; (S.L.); (N.D.); (A.C.)
| | - Sergio Bergese
- Department of Anesthesiology, Stony Brook University Hospital, Stony Brook, NY 11794, USA; (S.L.); (N.D.); (A.C.)
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3
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De Georgia M, Bowen T, Duncan KR, Chebl AB. Blood pressure management in ischemic stroke patients undergoing mechanical thrombectomy. Neurol Res Pract 2023; 5:12. [PMID: 36991520 PMCID: PMC10061853 DOI: 10.1186/s42466-023-00238-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 03/14/2023] [Indexed: 03/31/2023] Open
Abstract
The relationship between presenting blood pressure in acute ischemic stroke patients and outcome is complex. Several studies have demonstrated a U-shaped curve with worse outcomes when blood pressure is high or low. The American Heart Association/American Stroke Association guidelines recommend values of blood pressure < 185/110 mmHg in patients treated with intravenous t-PA and "permissive hypertension" up to 220/120 mmHg in those not treated with intravenous t-PA. The optimal blood pressure target is less clear in patients undergoing mechanical thrombectomy. Before thrombectomy, the guidelines recommend a blood pressure < 185/110 mmHg though patients with even lower systolic blood pressures may have better outcomes. During and after thrombectomy, the guidelines recommend a blood pressure < 180/105 mmHg. However, several studies have suggested that during thrombectomy the primary goal should be to prevent significant low blood pressure (e.g., target systolic blood pressure > 140 mmHg or MAP > 70 mmHg). After thrombectomy, the primary goal should be to prevent high blood pressure (e.g., target systolic blood pressure < 160 mmHg or MAP < 90 mmHg). To make more specific recommendations, large, randomized-control studies are needed that address factors such as the baseline blood pressure, timing and degree of revascularization, status of collaterals, and estimated risk of reperfusion injury.
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Affiliation(s)
- Michael De Georgia
- Department of Neurology, Case Western Reserve University School of Medicine, Cleveland, OH, USA.
| | - Theodore Bowen
- Department of Neurology, MetroHealth Medical Center, Cleveland, OH, USA
| | - K Rose Duncan
- Department of Neurology, Case Western Reserve University School of Medicine, Cleveland, OH, USA
| | - Alex Bou Chebl
- Department of Neurology, Henry Ford Medical Center, Detroit, MI, USA
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4
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Mahmoudzadeh M, Wallois F, Tir M, Krystkowiak P, Lefranc M. Cortical hemodynamic mapping of subthalamic nucleus deep brain stimulation in Parkinsonian patients, using high-density functional near-infrared spectroscopy. PLoS One 2021; 16:e0245188. [PMID: 33493171 PMCID: PMC7833160 DOI: 10.1371/journal.pone.0245188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 12/23/2020] [Indexed: 12/02/2022] Open
Abstract
Subthalamic nucleus deep brain stimulation (STN-DBS) is an effective treatment for idiopathic Parkinson's disease. Despite recent progress, the mechanisms responsible for the technique's effectiveness have yet to be fully elucidated. The purpose of the present study was to gain new insights into the interactions between STN-DBS and cortical network activity. We therefore combined high-resolution functional near-infrared spectroscopy with low-resolution electroencephalography in seven Parkinsonian patients on STN-DBS, and measured cortical haemodynamic changes at rest and during hand movement in the presence and absence of stimulation (the ON-stim and OFF-stim conditions, respectively) in the off-drug condition. The relative changes in oxyhaemoglobin [HbO], deoxyhaemoglobin [HbR], and total haemoglobin [HbT] levels were analyzed continuously. At rest, the [HbO], [HbR], and [HbT] over the bilateral sensorimotor (SM), premotor (PM) and dorsolateral prefrontal (DLPF) cortices decreased steadily throughout the duration of stimulation, relative to the OFF-stim condition. During hand movement in the OFF-stim condition, [HbO] increased and [HbR] decreased concomitantly over the contralateral SM cortex (as a result of neurovascular coupling), and [HbO], [HbR], and [HbT] increased concomitantly in the dorsolateral prefrontal cortex (DLPFC)-suggesting an increase in blood volume in this brain area. During hand movement with STN-DBS, the increase in [HbO] was over the contralateral SM and PM cortices was significantly lower than in the OFF-stim condition, as was the decrease in [HbO] and [HbT] in the DLPFC. Our results indicate that STN-DBS is associated with a reduction in blood volume over the SM, PM and DLPF cortices, regardless of whether or not the patient is performing a task. This particular effect on cortical networks might explain not only STN-DBS's clinical effectiveness but also some of the associated adverse effects.
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Affiliation(s)
| | | | - Mélissa Tir
- Neurosurgery Department, CHU Amiens-Picardie, Amiens, France
| | - Pierre Krystkowiak
- Neurology Department, CHU Amiens-Picardie, Amiens, France
- Laboratory of Functional Neurosciences, University of Picardie Jules Verne, Amiens, France
| | - Michel Lefranc
- Neurosurgery Department, CHU Amiens-Picardie, Amiens, France
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5
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Stretch syncope or epileptic seizure? A pathologic hypothesis for self-induced stretch syncope. Neurophysiol Clin 2020; 50:383-386. [PMID: 33172760 DOI: 10.1016/j.neucli.2020.08.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 08/14/2020] [Accepted: 08/14/2020] [Indexed: 11/21/2022] Open
Abstract
We report on a 7-year-old female who presented paroxysmal episodes of loss of consciousness with clonic movements. The electroencephalogram (EEG) evidenced diffuse slow wave activations, with no symptoms. Epilepsy was suspected but antiepileptic drugs were ineffective. Video-EEG monitoring revealed that the syncope was triggered by stretching with a tachycardia that started during the stretch maneuver and diffuse slow waves on the EEG 2s before the symptoms. Stretch syncope can result in striking manifestations with subcortically driven clonic movements that can be mistaken for signs of epilepsy. Stretching might lead to transient hypoxia of the brainstem; in turn, this might activate the thalamocortical loop and thus generate cardiovascular changes, EEG slow waves, and physical manifestations.
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6
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Drew PJ, Mateo C, Turner KL, Yu X, Kleinfeld D. Ultra-slow Oscillations in fMRI and Resting-State Connectivity: Neuronal and Vascular Contributions and Technical Confounds. Neuron 2020; 107:782-804. [PMID: 32791040 PMCID: PMC7886622 DOI: 10.1016/j.neuron.2020.07.020] [Citation(s) in RCA: 76] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 06/09/2020] [Accepted: 07/15/2020] [Indexed: 12/27/2022]
Abstract
Ultra-slow, ∼0.1-Hz variations in the oxygenation level of brain blood are widely used as an fMRI-based surrogate of "resting-state" neuronal activity. The temporal correlations among these fluctuations across the brain are interpreted as "functional connections" for maps and neurological diagnostics. Ultra-slow variations in oxygenation follow a cascade. First, they closely track changes in arteriole diameter. Second, interpretable functional connections arise when the ultra-slow changes in amplitude of γ-band neuronal oscillations, which are shared across even far-flung but synaptically connected brain regions, entrain the ∼0.1-Hz vasomotor oscillation in diameter of local arterioles. Significant confounds to estimates of functional connectivity arise from residual vasomotor activity as well as arteriole dynamics driven by self-generated movements and subcortical common modulatory inputs. Last, methodological limitations of fMRI can lead to spurious functional connections. The neuronal generator of ultra-slow variations in γ-band amplitude, including that associated with self-generated movements, remains an open issue.
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Affiliation(s)
- Patrick J Drew
- Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, PA 16802, USA; Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, USA; Department of Neurosurgery, Pennsylvania State University, University Park, PA 16802, USA
| | - Celine Mateo
- Department of Physics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kevin L Turner
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, USA
| | - Xin Yu
- High-Field Magnetic Resonance Department, Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany; MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA 02114, USA
| | - David Kleinfeld
- Department of Physics, University of California, San Diego, La Jolla, CA 92093, USA; Section of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA.
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7
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Cyr JP, Anctil N, Simoneau M. Balance control mechanisms do not benefit from successive stimulation of different sensory systems. PLoS One 2019; 14:e0226216. [PMID: 31826016 PMCID: PMC6905548 DOI: 10.1371/journal.pone.0226216] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 11/21/2019] [Indexed: 11/19/2022] Open
Abstract
In humans, to reduce deviations from a perfect upright position, information from various sensory cues is combined and continuously weighted based on its reliability. Combining noisy sensory information to produce a coherent and accurate estimate of body sway is a central problem in human balance control. In this study, we first compared the ability of the sensorimotor control mechanisms to deal with altered ankle proprioception or vestibular information (i.e., the single sensory condition). Then, we evaluated whether successive stimulation of difference sensory systems (e.g., Achilles tendon vibration followed by electrical vestibular stimulation, or vice versa) produced a greater alteration of balance control (i.e., the mix sensory condition). Electrical vestibular stimulation (head turned ~90°) and Achilles tendon vibration induced backward body sways. We calculated the root mean square value of the scalar distance between the center of pressure and the center of gravity as well as the time needed to regain balance (i.e., stabilization time). Furthermore, the peak ground reaction force along the anteroposterior axis, immediately following stimulation offset, was determined to compare the balance destabilization across the different conditions. In single conditions, during vestibular or Achilles tendon vibration, no difference in balance control was observed. When sensory information returned to normal, balance control was worse following Achilles tendon vibration. Compared to that of the single sensory condition, successive stimulation of different sensory systems (i.e., mix conditions) increased stabilization time. Overall, the present results reveal that single and successive sensory stimulation challenges the sensorimotor control mechanisms differently.
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Affiliation(s)
- Jean-Philippe Cyr
- Département de kinésiologie, Faculté de médecine, Université Laval, Québec, Québec, Canada
- Centre interdisciplinaire de recherche en réadaptation et intégration sociale (CIRRIS) du CIUSSS de la Capitale Nationale, Québec, Québec, Canada
| | - Noémie Anctil
- Département de kinésiologie, Faculté de médecine, Université Laval, Québec, Québec, Canada
- Centre interdisciplinaire de recherche en réadaptation et intégration sociale (CIRRIS) du CIUSSS de la Capitale Nationale, Québec, Québec, Canada
| | - Martin Simoneau
- Département de kinésiologie, Faculté de médecine, Université Laval, Québec, Québec, Canada
- Centre interdisciplinaire de recherche en réadaptation et intégration sociale (CIRRIS) du CIUSSS de la Capitale Nationale, Québec, Québec, Canada
- * E-mail:
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8
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Lombardi C, Pengo MF, Parati G. Obstructive sleep apnea syndrome and autonomic dysfunction. Auton Neurosci 2019; 221:102563. [PMID: 31445406 DOI: 10.1016/j.autneu.2019.102563] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 05/23/2019] [Accepted: 07/09/2019] [Indexed: 01/29/2023]
Abstract
Autonomic nervous system (ANS) has been extensively explored in obstructive sleep apnea (OSA). Autonomic alterations in these patients have been described by means of several methods, evaluating ANS function both directly with microneurography and indirectly through baroreflex sensitivity (BRS, by the sequence method or the cross-spectral approach), heart rate variability analysis (HRV, both in the time and frequency domain) during sleep and wake, or conventional laboratory tests, including cold pressor test, hand grip test or measurement of urinary cathecolamine excretion. Several studies in OSA patients have shown ANS alterations, in particular sympathetic overactivity, both acutely during apnea events and chronically during the daytime, being both also involved in cardiovascular consequences of sleep disordered breathing. The association between OSA and sympathetic dysregulation suggests a dose response relationship between OSA severity and the degree of sympathetic overactivity and this association seems to be reversible as the treatment of OSA is implemented. Additionally ANS is involved in regulating visceral and humoral functions to maintain the body homeostasis and in reaction and adaptation to external and internal stressor stimuli. However, the vast majority of studies have focussed on cardiovascular alterations, which are easier to measure, somewhat neglecting the other functions regulated by ANS. More evidence is therefore needed to better characterize the impact that sleep disorder breathing may have on ANS both in the short and long term.
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Affiliation(s)
- C Lombardi
- Istituto Auxologico Italiano, IRCCS, Sleep Disorders Center & Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital, Milan, Italy; Department of Medicine and Surgery, University of Milano-Bicocca, Milan, Italy.
| | - M F Pengo
- Istituto Auxologico Italiano, IRCCS, Sleep Disorders Center & Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital, Milan, Italy
| | - G Parati
- Istituto Auxologico Italiano, IRCCS, Sleep Disorders Center & Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital, Milan, Italy; Department of Medicine and Surgery, University of Milano-Bicocca, Milan, Italy
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9
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Grimaldi D, Papalambros NA, Reid KJ, Abbott SM, Malkani RG, Gendy M, Iwanaszko M, Braun RI, Sanchez DJ, Paller KA, Zee PC. Strengthening sleep-autonomic interaction via acoustic enhancement of slow oscillations. Sleep 2019; 42:zsz036. [PMID: 30753650 PMCID: PMC7729207 DOI: 10.1093/sleep/zsz036] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 01/25/2019] [Indexed: 11/14/2022] Open
Abstract
Slow-wave sleep (SWS) is important for overall health since it affects many physiological processes including cardio-metabolic function. Sleep and autonomic nervous system (ANS) activity are closely coupled at anatomical and physiological levels. Sleep-related changes in autonomic function are likely the main pathway through which SWS affects many systems within the body. There are characteristic changes in ANS activity across sleep stages. Notably, in non-rapid eye-movement sleep, the progression into SWS is characterized by increased parasympathetic activity, an important measure of cardiovascular health. Experimental manipulations that enhance slow-wave activity (SWA, 0.5-4 Hz) can improve sleep-mediated memory and immune function. However, effects of SWA enhancement on autonomic regulation have not been investigated. Here, we employed an adaptive algorithm to deliver 50 ms sounds phase-locked to slow-waves, with regular pauses in stimulation (~5 s ON/~5 s OFF), in healthy young adults. We sought to determine whether acoustic enhancement of SWA altered parasympathetic activity during SWS assessed with heart rate variability (HRV), and evening-to-morning changes in HRV, plasma cortisol, and blood pressure. Stimulation, compared with a sham condition, increased SWA during ON versus OFF intervals. This ON/OFF SWA enhancement was associated with a reduction in evening-to-morning change of cortisol levels and indices of sympathetic activity. Furthermore, the enhancement of SWA in ON intervals during sleep cycles 2-3 was accompanied by an increase in parasympathetic activity (high-frequency, HRV). Together these findings suggest that acoustic enhancement of SWA has a positive effect on autonomic function in sleep. Approaches to strengthen brain-heart interaction during sleep could have important implications for cardiovascular health.
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Affiliation(s)
- Daniela Grimaldi
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL
| | - Nelly A Papalambros
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL
| | - Kathryn J Reid
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL
| | - Sabra M Abbott
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL
| | - Roneil G Malkani
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL
| | - Maged Gendy
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL
| | - Marta Iwanaszko
- Biostatistics Division, Feinberg School of Medicine, Northwestern University, Chicago, IL
| | - Rosemary I Braun
- Biostatistics Division, Feinberg School of Medicine, Northwestern University, Chicago, IL
- Department of Engineering Sciences and Applied Mathematics, Northwestern University, Evanston, IL
| | | | - Ken A Paller
- Department of Psychology, Northwestern University, Evanston, IL
| | - Phyllis C Zee
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL
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10
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Reiner A, Fitzgerald MEC, Del Mar N, Li C. Neural control of choroidal blood flow. Prog Retin Eye Res 2018; 64:96-130. [PMID: 29229444 PMCID: PMC5971129 DOI: 10.1016/j.preteyeres.2017.12.001] [Citation(s) in RCA: 121] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 11/28/2017] [Accepted: 12/01/2017] [Indexed: 02/07/2023]
Abstract
The choroid is richly innervated by parasympathetic, sympathetic and trigeminal sensory nerve fibers that regulate choroidal blood flow in birds and mammals, and presumably other vertebrate classes as well. The parasympathetic innervation has been shown to vasodilate and increase choroidal blood flow, the sympathetic input has been shown to vasoconstrict and decrease choroidal blood flow, and the sensory input has been shown to both convey pain and thermal information centrally and act locally to vasodilate and increase choroidal blood flow. As the choroid lies behind the retina and cannot respond readily to retinal metabolic signals, its innervation is important for adjustments in flow required by either retinal activity, by fluctuations in the systemic blood pressure driving choroidal perfusion, and possibly by retinal temperature. The former two appear to be mediated by the sympathetic and parasympathetic nervous systems, via central circuits responsive to retinal activity and systemic blood pressure, but adjustments for ocular perfusion pressure also appear to be influenced by local autoregulatory myogenic mechanisms. Adaptive choroidal responses to temperature may be mediated by trigeminal sensory fibers. Impairments in the neural control of choroidal blood flow occur with aging, and various ocular or systemic diseases such as glaucoma, age-related macular degeneration (AMD), hypertension, and diabetes, and may contribute to retinal pathology and dysfunction in these conditions, or in the case of AMD be a precondition. The present manuscript reviews findings in birds and mammals that contribute to the above-summarized understanding of the roles of the autonomic and sensory innervation of the choroid in controlling choroidal blood flow, and in the importance of such regulation for maintaining retinal health.
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Affiliation(s)
- Anton Reiner
- Department of Anatomy & Neurobiology, University of Tennessee, 855 Monroe Ave. Memphis, TN 38163, United States; Department of Ophthalmology, University of Tennessee, 855 Monroe Ave. Memphis, TN 38163, United States.
| | - Malinda E C Fitzgerald
- Department of Anatomy & Neurobiology, University of Tennessee, 855 Monroe Ave. Memphis, TN 38163, United States; Department of Ophthalmology, University of Tennessee, 855 Monroe Ave. Memphis, TN 38163, United States; Department of Biology, Christian Brothers University, Memphis, TN, United States
| | - Nobel Del Mar
- Department of Anatomy & Neurobiology, University of Tennessee, 855 Monroe Ave. Memphis, TN 38163, United States
| | - Chunyan Li
- Department of Anatomy & Neurobiology, University of Tennessee, 855 Monroe Ave. Memphis, TN 38163, United States
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11
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Mubeen AM, Ardekani B, Tagliati M, Alterman R, Dhawan V, Eidelberg D, Sidtis JJ. Global and multi-focal changes in cerebral blood flow during subthalamic nucleus stimulation in Parkinson's disease. J Cereb Blood Flow Metab 2018; 38:697-705. [PMID: 28421851 PMCID: PMC5888853 DOI: 10.1177/0271678x17705042] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Electrical stimulation of subthalamic nuclei (STN) is a widely used therapy in Parkinson's disease (PD). While deep brain stimulation (DBS) of the STN alters the neurophysiological activity in basal ganglia, the therapeutic mechanism has not been established. A positron emission tomography (PET) study of cerebral blood flow (CBF) during speech production in PD subjects treated with STN-DBS found significant increases in global (whole-brain) CBF.1 That study utilized a series of whole-slice regions of interest to obtain global CBF values. The present study examined this effect using a voxel-based principal component analysis (PCA) combined with Fisher's linear discriminant analysis (FLDA) to classify STN-DBS on versus STN-DBS off whole-brain images. The approach yielded wide-spread CBF changes that classified STN-DBS status with accuracy, sensitivity, and specificity approaching 90%. The PCA component of the analysis supported the observation of a global CBF change during STN-DBS. The FLDA component demonstrated wide-spread multi-focal CBF changes. Further, CBF measurements related to a number of subject characteristics when STN-DBS was off, but not when it was on, suggesting that the normal relationship between CBF and behavior may be disrupted by this form of neuromodulation.
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Affiliation(s)
- Asim M Mubeen
- 1 Brain and Behavior Laboratory, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
| | - Babak Ardekani
- 2 Center for Brain Imaging and Neuromodulation, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
| | - Michele Tagliati
- 3 Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Ron Alterman
- 4 Division of Neurosurgery, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | | | | | - John J Sidtis
- 1 Brain and Behavior Laboratory, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, USA
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12
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Lecci S, Fernandez LMJ, Weber FD, Cardis R, Chatton JY, Born J, Lüthi A. Coordinated infraslow neural and cardiac oscillations mark fragility and offline periods in mammalian sleep. SCIENCE ADVANCES 2017; 3:e1602026. [PMID: 28246641 PMCID: PMC5298853 DOI: 10.1126/sciadv.1602026] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 12/19/2016] [Indexed: 05/05/2023]
Abstract
Rodents sleep in bouts lasting minutes; humans sleep for hours. What are the universal needs served by sleep given such variability? In sleeping mice and humans, through monitoring neural and cardiac activity (combined with assessment of arousability and overnight memory consolidation, respectively), we find a previously unrecognized hallmark of sleep that balances two fundamental yet opposing needs: to maintain sensory reactivity to the environment while promoting recovery and memory consolidation. Coordinated 0.02-Hz oscillations of the sleep spindle band, hippocampal ripple activity, and heart rate sequentially divide non-rapid eye movement (non-REM) sleep into offline phases and phases of high susceptibility to external stimulation. A noise stimulus chosen such that sleeping mice woke up or slept through at comparable rates revealed that offline periods correspond to raising, whereas fragility periods correspond to declining portions of the 0.02-Hz oscillation in spindle activity. Oscillations were present throughout non-REM sleep in mice, yet confined to light non-REM sleep (stage 2) in humans. In both species, the 0.02-Hz oscillation predominated over posterior cortex. The strength of the 0.02-Hz oscillation predicted superior memory recall after sleep in a declarative memory task in humans. These oscillations point to a conserved function of mammalian non-REM sleep that cycles between environmental alertness and internal memory processing in 20- to 25-s intervals. Perturbed 0.02-Hz oscillations may cause memory impairment and ill-timed arousals in sleep disorders.
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Affiliation(s)
- Sandro Lecci
- Department of Fundamental Neurosciences, University of Lausanne, 1005 Lausanne, Switzerland
| | - Laura M. J. Fernandez
- Department of Fundamental Neurosciences, University of Lausanne, 1005 Lausanne, Switzerland
| | - Frederik D. Weber
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, 72076 Tübingen, Germany
| | - Romain Cardis
- Department of Fundamental Neurosciences, University of Lausanne, 1005 Lausanne, Switzerland
| | - Jean-Yves Chatton
- Department of Fundamental Neurosciences, University of Lausanne, 1005 Lausanne, Switzerland
| | - Jan Born
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, 72076 Tübingen, Germany
| | - Anita Lüthi
- Department of Fundamental Neurosciences, University of Lausanne, 1005 Lausanne, Switzerland
- Corresponding author.
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Golanov EV, Shiflett JM, Britz GW. Diving Response in Rats: Role of the Subthalamic Vasodilator Area. Front Neurol 2016; 7:157. [PMID: 27708614 PMCID: PMC5030511 DOI: 10.3389/fneur.2016.00157] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 09/08/2016] [Indexed: 11/29/2022] Open
Abstract
Diving response (DR) is a powerful integrative response targeted toward survival of the hypoxic/anoxic conditions. Being present in all animals and humans, it allows to survive adverse conditions like diving. Earlier, we discovered that forehead stimulation affords neuroprotective effect, decreasing infarction volume triggered by permanent occlusion of the middle cerebral artery in rats. We hypothesized that cold stimulation of the forehead induces DR in rats, which, in turn, exerts neuroprotection. We compared autonomic [AP, heart rate (HR), cerebral blood flow (CBF)] and EEG responses to the known DR-triggering stimulus, ammonia stimulation of the nasal mucosa, cold stimulation of the forehead, and cold stimulation of the glabrous skin of the tail base in anesthetized rats. Responses in AP, HR, CBF, and EEG to cold stimulation of the forehead and ammonia vapors instillation into the nasal cavity were comparable and differed significantly from responses to the cold stimulation of the tail base. Excitotoxic lesion of the subthalamic vasodilator area (SVA), which is known to participate in CBF regulation and to afford neuroprotection upon excitation, failed to affect autonomic components of the DR evoked by forehead cold stimulation or nasal mucosa ammonia stimulation. We conclude that cold stimulation of the forehead triggers physiological response comparable to the response evoked by ammonia vapor instillation into nasal cavity, which is considered as stimulus triggering protective DR. These observations may explain the neuroprotective effect of the forehead stimulation. Data demonstrate that SVA does not directly participate in the autonomic adjustments accompanying DR; however, it is involved in diving-evoked modulation of EEG. We suggest that forehead stimulation can be employed as a stimulus capable of triggering oxygen-conserving DR and can be used for neuroprotective therapy.
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Affiliation(s)
- Eugene V. Golanov
- Department of Neurosurgery, The Houston Methodist Hospital, Houston, TX, USA
- Department of Neurosurgery, University of Mississippi Medical Center, Jackson, MS, USA
| | - James M. Shiflett
- Department of Neurosurgery, University of Mississippi Medical Center, Jackson, MS, USA
| | - Gavin W. Britz
- Department of Neurosurgery, The Houston Methodist Hospital, Houston, TX, USA
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Critchley HD, Nicotra A, Chiesa PA, Nagai Y, Gray MA, Minati L, Bernardi L. Slow breathing and hypoxic challenge: cardiorespiratory consequences and their central neural substrates. PLoS One 2015; 10:e0127082. [PMID: 25973923 PMCID: PMC4431729 DOI: 10.1371/journal.pone.0127082] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Accepted: 04/11/2015] [Indexed: 11/19/2022] Open
Abstract
Controlled slow breathing (at 6/min, a rate frequently adopted during yoga practice) can benefit cardiovascular function, including responses to hypoxia. We tested the neural substrates of cardiorespiratory control in humans during volitional controlled breathing and hypoxic challenge using functional magnetic resonance imaging (fMRI). Twenty healthy volunteers were scanned during paced (slow and normal rate) breathing and during spontaneous breathing of normoxic and hypoxic (13% inspired O2) air. Cardiovascular and respiratory measures were acquired concurrently, including beat-to-beat blood pressure from a subset of participants (N = 7). Slow breathing was associated with increased tidal ventilatory volume. Induced hypoxia raised heart rate and suppressed heart rate variability. Within the brain, slow breathing activated dorsal pons, periaqueductal grey matter, cerebellum, hypothalamus, thalamus and lateral and anterior insular cortices. Blocks of hypoxia activated mid pons, bilateral amygdalae, anterior insular and occipitotemporal cortices. Interaction between slow breathing and hypoxia was expressed in ventral striatal and frontal polar activity. Across conditions, within brainstem, dorsal medullary and pontine activity correlated with tidal volume and inversely with heart rate. Activity in rostroventral medulla correlated with beat-to-beat blood pressure and heart rate variability. Widespread insula and striatal activity tracked decreases in heart rate, while subregions of insular cortex correlated with momentary increases in tidal volume. Our findings define slow breathing effects on central and cardiovascular responses to hypoxic challenge. They highlight the recruitment of discrete brainstem nuclei to cardiorespiratory control, and the engagement of corticostriatal circuitry in support of physiological responses that accompany breathing regulation during hypoxic challenge.
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Affiliation(s)
- Hugo D. Critchley
- Brighton and Sussex Medical School, University of Sussex, Brighton, United Kingdom
- Sackler Centre for Consciousness Science, University of Sussex, Brighton, United Kingdom
- * E-mail:
| | - Alessia Nicotra
- Imperial College Healthcare NHS Trust, London, United Kingdom
| | - Patrizia A. Chiesa
- Department of Psychology, Sapienza University of Rome, Rome, Italy
- Ghermann Laboratory, University of Queensland, Queensland, Australia
| | - Yoko Nagai
- Brighton and Sussex Medical School, University of Sussex, Brighton, United Kingdom
| | | | | | - Luciano Bernardi
- Department of Internal Medicine, University of Pavia and Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
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Cetas JS, McFarlane R, Kronfeld K, Smitasin P, Liu JJ, Raskin JS. Brainstem Opioidergic System Is Involved in Early Response to Experimental SAH. Transl Stroke Res 2014; 6:140-7. [DOI: 10.1007/s12975-014-0378-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 10/22/2014] [Accepted: 11/13/2014] [Indexed: 01/21/2023]
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Gaston B, May WJ, Sullivan S, Yemen S, Marozkina NV, Palmer LA, Bates JN, Lewis SJ. Essential role of hemoglobin beta-93-cysteine in posthypoxia facilitation of breathing in conscious mice. J Appl Physiol (1985) 2014; 116:1290-9. [PMID: 24610531 DOI: 10.1152/japplphysiol.01050.2013] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
When erythrocyte hemoglobin (Hb) is fully saturated with O2, nitric oxide (NO) covalently binds to the cysteine 93 residue of the Hb β-chain (B93-CYS), forming S-nitrosohemoglobin. Binding of NO is allosterically coupled to the O2 saturation of Hb. As saturation falls, the NO group on B93-CYS is transferred to thiols in the erythrocyte, and in the plasma, forming circulating S-nitrosothiols. Here, we studied whether the changes in ventilation during and following exposure to a hypoxic challenge were dependent on erythrocytic B93-CYS. Studies were performed in conscious mice in which native murine Hb was replaced with human Hb (hB93-CYS mice) and in mice in which murine Hb was replaced with human Hb containing an alanine rather than cysteine at position 93 on the Bchain (hB93-ALA). Both strains expressed human γ-chain Hb, likely allowing a residual element of S-nitrosothiol-dependent signaling. While resting parameters and initial hypoxic (10% O2, 90% N2) ventilatory responses were similar in hB93-CYS mice and hB93-ALA mice, the excitatory ventilatory responses (short-term potentiation) that occurred once the mice were returned to room air were markedly diminished in hB93-ALA mice. Further, short-term potentiation responses were virtually absent in mice with bilateral transection of the carotid sinus nerves. These data demonstrate that hB93-CYS plays an essential role in mediating carotid sinus nerve-dependent short-term potentiation, an important mechanism for recovery from acute hypoxia.
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Affiliation(s)
- Benjamin Gaston
- Pediatric Respiratory Medicine, University of Virginia School of Medicine, Charlottesville, Virginia;
| | - Walter J May
- Pediatric Respiratory Medicine, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Spencer Sullivan
- Pediatric Respiratory Medicine, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Sean Yemen
- Pediatric Respiratory Medicine, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Nadzeya V Marozkina
- Pediatric Respiratory Medicine, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Lisa A Palmer
- Pediatric Respiratory Medicine, University of Virginia School of Medicine, Charlottesville, Virginia
| | - James N Bates
- Department of Anesthesia, University of Iowa Hospitals and Clinics, Iowa City, Iowa; and
| | - Stephen J Lewis
- Department of Pediatrics, Rainbow Babies and Children's Hospital, Cleveland, Ohio
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Zeredo ZL, Toda K, Kumei Y. Neuronal Activity in the Subthalamic Cerebrovasodilator Area under Partial-Gravity Conditions in Rats. Life (Basel) 2014; 4:107-16. [PMID: 25370031 PMCID: PMC4187145 DOI: 10.3390/life4010107] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 02/18/2014] [Accepted: 02/26/2014] [Indexed: 01/23/2023] Open
Abstract
The reduced-gravity environment in space is known to cause an upward shift in body fluids and thus require cardiovascular adaptations in astronauts. In this study, we recorded in rats the neuronal activity in the subthalamic cerebrovasodilator area (SVA), a key area that controls cerebral blood flow (CBF), in response to partial gravity. “Partial gravity” is the term that defines the reduced-gravity levels between 1 g (the unit gravity acceleration on Earth) and 0 g (complete weightlessness in space). Neuronal activity was recorded telemetrically through chronically implanted microelectrodes in freely moving rats. Graded levels of partial gravity from 0.4 g to 0.01 g were generated by customized parabolic-flight maneuvers. Electrophysiological signals in each partial-gravity phase were compared to those of the preceding 1 g level-flight. As a result, SVA neuronal activity was significantly inhibited by the partial-gravity levels of 0.15 g and lower, but not by 0.2 g and higher. Gravity levels between 0.2–0.15 g could represent a critical threshold for the inhibition of neurons in the rat SVA. The lunar gravity (0.16 g) might thus trigger neurogenic mechanisms of CBF control. This is the first study to examine brain electrophysiology with partial gravity as an experimental parameter.
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Affiliation(s)
- Zeredo L Zeredo
- Graduate School, Tokyo Medical and Dental University, Tokyo 113-8549, Japan.
| | - Kazuo Toda
- Graduate School, Nagasaki University, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan.
| | - Yasuhiro Kumei
- Graduate School, Tokyo Medical and Dental University, Tokyo 113-8549, Japan.
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Ward NL, Lamanna JC. The neurovascular unit and its growth factors: coordinated response in the vascular and nervous systems. Neurol Res 2013; 26:870-83. [PMID: 15727271 DOI: 10.1179/016164104x3798] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The nervous and vascular systems contain many common organizational features and develop similarly in terms of anatomical patterning. During embryogenesis and in regions of the brain undergoing postnatal neurogenesis, neural stem cells and endothelial cells are found in close proximity, or within a so-called vascular niche. The similarities in patterning and proximity may reflect coordinated development based on responsiveness to similar growth factors such as vascular endothelial growth factor, semaphorin, and ephrins/Ephs: molecules involved in the development and maintenance of both the nervous and vascular systems. Despite the blatant similarities between the vascular and nervous systems, little is still known about the co-dependence and/or interactions between the two systems during development and following alterations in metabolic demand as seen during aging, exercise, and disease processes. The interactions between the two systems involving common growth factors suggest these two systems have evolved in an interconnected way.
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Affiliation(s)
- Nicole L Ward
- Department of Anatomy, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA.
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Zanatta P, Toffolo GM, Sartori E, Bet A, Baldanzi F, Agarwal N, Golanov E. The human brain pacemaker: Synchronized infra-slow neurovascular coupling in patients undergoing non-pulsatile cardiopulmonary bypass. Neuroimage 2013; 72:10-9. [DOI: 10.1016/j.neuroimage.2013.01.033] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 01/17/2013] [Accepted: 01/20/2013] [Indexed: 11/27/2022] Open
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Abstract
Mental processes and their neural substrates are intimately linked to the homeostatic control of internal bodily state. There are a set of distinct interoceptive pathways that directly and indirectly influence brain functions. The anatomical organization of these pathways and the psychological/behavioral expressions of their influence appear along discrete, evolutionarily conserved dimensions that are tractable to a mechanistic understanding. Here, we review the role of these pathways as sources of biases to perception, cognition, emotion, and behavior and arguably the dynamic basis to the concept of self.
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Affiliation(s)
- Hugo D Critchley
- Psychiatry, Brighton and Sussex Medical School, Brighton BN1 9RR, UK.
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Can Mitochondrial Cytochrome Oxidase Mediate Hypoxic Vasodilation Via Nitric Oxide Metabolism? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 765:231-238. [DOI: 10.1007/978-1-4614-4989-8_32] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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23
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Mandel M, Talamoni Fonoff E, Bor-Seng-Shu E, Teixeira MJ, Chadi G. Neurogenic neuroprotection: clinical perspectives. FUNCTIONAL NEUROLOGY 2012; 27:207-16. [PMID: 23597434 PMCID: PMC3861344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Neurogenic neuroprotection is a promising approach for treating patients with ischemic brain lesions. In rats, stimulation of the deep brain nuclei has been shown to reduce the volume of focal infarction. In this context, protection of neural tissue can be a rapid intervention that has a relatively long-lasting effect, making fastigial nucleus stimulation (FNS) a potentially valuable method for clinical application. Although the mechanisms of neuroprotection induced by FNS remain partially unclear, important data have been presented in the last two decades. A 1-h electrical FNS reduced, by 59%, infarctions triggered by permanent occlusion of the middle cerebral artery in Fisher rats. The acute effect of electrical FNS is likely mediated by a prolonged opening of potassium channels, and the sustained effect appears to be linked to inhibition of the apoptotic cascade. A better understanding of the neuronal circuitry underlying neurogenic neuroprotection may contribute to improving neurological outcomes in ischemic brain insults.
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Affiliation(s)
- Mauricio Mandel
- Department of Neurology, University of São Paulo School of Medicine, São Paulo, Brazil.
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24
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Therapeutic high-frequency stimulation of the subthalamic nucleus in Parkinson's disease produces global increases in cerebral blood flow. J Cereb Blood Flow Metab 2012; 32:41-9. [PMID: 21971352 PMCID: PMC3323302 DOI: 10.1038/jcbfm.2011.135] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Chronic, high-frequency electrical stimulation of the subthalamic nuclei (STNs) has become an effective and widely used therapy in Parkinson's disease (PD), but the therapeutic mechanism is not understood. Stimulation of the STN is believed to reorganize neurophysiological activity patterns within the basal ganglia, whereas local field effects extending to tracts adjacent to the STN are viewed as sources of nontherapeutic side effects. This study is part of a larger project investigating the effects of STN stimulation on speech and regional cerebral blood flow (CBF) in human subjects with PD. While generating measures of global CBF (gCBF) to normalize regional CBF values for a subsequent combined analysis of regional CBF and speech data, we observed a third effect of this therapy: a gCBF increase. This effect was present across three estimates of gCBF ranging from values based on the highest activity voxels to those based on all voxels. The magnitude of the gCBF increase was related to the subject's duration of PD. It is not clear whether this CBF effect has a therapeutic role, but the impact of deep brain stimulation on cerebrovascular control warrants study from neuroscience, pathophysiological, and therapeutic perspectives.
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25
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Petzold GC, Murthy VN. Role of astrocytes in neurovascular coupling. Neuron 2011; 71:782-97. [PMID: 21903073 DOI: 10.1016/j.neuron.2011.08.009] [Citation(s) in RCA: 285] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/15/2011] [Indexed: 10/17/2022]
Abstract
Neural activity is intimately tied to blood flow in the brain. This coupling is specific enough in space and time that modern imaging methods use local hemodynamics as a measure of brain activity. In this review, we discuss recent evidence indicating that neuronal activity is coupled to local blood flow changes through an intermediary, the astrocyte. We highlight unresolved issues regarding the role of astrocytes and propose ways to address them using novel techniques. Our focus is on cellular level analysis in vivo, but we also relate mechanistic insights gained from ex vivo experiments to native tissue. We also review some strategies to harness advances in optical and genetic methods to study neurovascular coupling in the intact brain.
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Affiliation(s)
- Gabor C Petzold
- German Center for Neurodegenerative Diseases (DZNE), Ludwig-Erhard-Allee 2, 53175 Bonn, Germany.
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26
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Performance-based connectivity analysis: a path to convergence with clinical studies. Neuroimage 2011; 59:2316-21. [PMID: 21963910 DOI: 10.1016/j.neuroimage.2011.09.037] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2011] [Revised: 09/12/2011] [Accepted: 09/14/2011] [Indexed: 11/24/2022] Open
Abstract
Connectivity analyses have become increasingly important in functional imaging. When used to describe the functional anatomy of a specific behavior, these analyses are generally applied to a subset of the data that demonstrate significant differences when experimental conditions are contrasted. Such data reduction is sub-optimal for a systems approach as it assumes that all data that survive the statistical contrast filter are related to the behavior and that none of the filtered data has a significant function. When such data filtering is applied to speech and language tasks, the resulting functional anatomy rarely reflects the brain lateralization established in over a century and a half of clinical studies. A two-step performance-based connectivity analysis is described in which the first step uses multiple linear regression to establish a direct relationship between regional brain activity and a measure of performance. The second step uses partial correlations to examine the functional relationships between the predictor regions and other brain regions. When applied to regional cerebral blood flow data obtained with positron emission tomography during a speech production task, the results demonstrate left lateralization of motor control areas, thalamic involvement in repetition rate, and auditory cortical suppression, all consistent with clinical observations. The integration of performance measures into the earliest stages of image analysis without reliance on data filtering based on decomposition may provide a path toward convergence with traditional descriptions of functional anatomy based on clinical studies.
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Lucas SJE, Burgess KR, Thomas KN, Donnelly J, Peebles KC, Lucas RAI, Fan JL, Cotter JD, Basnyat R, Ainslie PN. Alterations in cerebral blood flow and cerebrovascular reactivity during 14 days at 5050 m. J Physiol 2010; 589:741-53. [PMID: 21041534 PMCID: PMC3052440 DOI: 10.1113/jphysiol.2010.192534] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Upon ascent to high altitude, cerebral blood flow (CBF) rises substantially before returning to sea-level values. The underlying mechanisms for these changes are unclear. We examined three hypotheses: (1) the balance of arterial blood gases upon arrival at and across 2 weeks of living at 5050 m will closely relate to changes in CBF; (2) CBF reactivity to steady-state changes in CO2 will be reduced following this 2 week acclimatisation period, and (3) reductions in CBF reactivity to CO2 will be reflected in an augmented ventilatory sensitivity to CO2. We measured arterial blood gases, middle cerebral artery blood flow velocity (MCAv, index of CBF) and ventilation () at rest and during steady-state hyperoxic hypercapnia (7% CO2) and voluntary hyperventilation (hypocapnia) at sea level and then again following 2–4, 7–9 and 12–15 days of living at 5050 m. Upon arrival at high altitude, resting MCAv was elevated (up 31 ± 31%; P < 0.01; vs. sea level), but returned to sea-level values within 7–9 days. Elevations in MCAv were strongly correlated (R2= 0.40) with the change in ratio (i.e. the collective tendency of arterial blood gases to cause CBF vasodilatation or constriction). Upon initial arrival and after 2 weeks at high altitude, cerebrovascular reactivity to hypercapnia was reduced (P < 0.05), whereas hypocapnic reactivity was enhanced (P < 0.05 vs. sea level). Ventilatory response to hypercapnia was elevated at days 2–4 (P < 0.05 vs. sea level, 4.01 ± 2.98 vs. 2.09 ± 1.32 l min−1 mmHg−1). These findings indicate that: (1) the balance of arterial blood gases accounts for a large part of the observed variability (∼40%) leading to changes in CBF at high altitude; (2) cerebrovascular reactivity to hypercapnia and hypocapnia is differentially affected by high-altitude exposure and remains distorted during partial acclimatisation, and (3) alterations in cerebrovascular reactivity to CO2 may also affect ventilatory sensitivity.
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Affiliation(s)
- Samuel J E Lucas
- Department of Physiology, University of Otago, Dunedin, New Zealand.
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Azevedo E, Santos R, Freitas J, Rosas MJ, Gago M, Garrett C, Rosengarten B. Deep brain stimulation does not change neurovascular coupling in non-motor visual cortex: an autonomic and visual evoked blood flow velocity response study. Parkinsonism Relat Disord 2010; 16:600-3. [PMID: 20846894 DOI: 10.1016/j.parkreldis.2010.08.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Revised: 07/24/2010] [Accepted: 08/23/2010] [Indexed: 11/25/2022]
Abstract
BACKGROUND AND PURPOSE In Parkinson's disease (PD) subthalamic nucleus deep brain stimulation (STN-DBS) improves motor function. Also an effect on the neurovascular coupling in motor cortex was reported due to a parallel activation of a subthalamic vasodilator area (SVA). To address this issue further we analysed neurovascular coupling in a non-motor area. METHODS Twenty PD patients selected for bilateral STN-DBS were investigated with functional transcranial Doppler (f-TCD) before and after surgery. Hemodynamic responses to visual stimulation were registered in left posterior cerebral artery (PCA) and analysed with a control-system approach (parameters gain, rate time, attenuation and natural frequency). To exclude autonomic effects of STN-DBS, we also addressed spectrum analysis of heart rate and of systolic arterial blood pressure variability, and baroreceptor gain. Findings in the PD group were compared with healthy age-matched controls. RESULTS PD patients showed no neurovascular coupling changes in PCA territory, compared to controls, and STN-DBS changed neither blood flow regulatory parameters nor autonomic function. CONCLUSIONS Improvement of vasoregulation in some motor cortical areas after STN-DBS might be related to an improved neuronal functional rather than indicating an effect on the neurovascular coupling or autonomic function.
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Affiliation(s)
- Elsa Azevedo
- Department of Neurology, Hospital São João and Faculty of Medicine of University of Porto, Alameda Professor Hernani Monteiro, 4202-451 Porto, Portugal.
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29
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Areza-Fegyveres R, Kairalla RA, Carvalho CRR, Nitrini R. Cognition and chronic hypoxia in pulmonary diseases. Dement Neuropsychol 2010; 4:14-22. [PMID: 29213655 PMCID: PMC5619525 DOI: 10.1590/s1980-57642010dn40100003] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Lung disease with chronic hypoxia has been associated with cognitive impairment
of the subcortical type.
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Affiliation(s)
- Renata Areza-Fegyveres
- Neurologist, collaborating researcher of the Cognitive and Behavioral Neurology Unit, Hospital das Clínicas, University of São Paulo Medical School
| | - Ronaldo A Kairalla
- Assistant Professor, Pulmonary Division, Heart Institute (InCor), University of São Paulo Medical School
| | - Carlos R R Carvalho
- Associate Professor, Pulmonary Division, Heart Institute (InCor), University of São Paulo Medical School
| | - Ricardo Nitrini
- Associate Professor of the Department of Neurology and Director of the Cognitive and Behavioral Neurology Unit, Hospital das Clínicas, University of São Paulo Medical School
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Ainslie PN, Ogoh S. Regulation of cerebral blood flow in mammals during chronic hypoxia: a matter of balance. Exp Physiol 2009; 95:251-62. [PMID: 19617269 DOI: 10.1113/expphysiol.2008.045575] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Respiratory-induced changes in the partial pressures of arterial carbon dioxide (PaCO2) and oxygen (PaO2) play a major role in cerebral blood flow (CBF) regulation. Elevations in PaCO2 (hypercapnia) lead to vasodilatation and increases in CBF, whereas reductions in PaCO2 (hypocapnia) lead to vasoconstriction and decreases in CBF. A fall in PaO2 (hypoxia) below a certain threshold (<40-45 mmHg) also produces cerebral vasodilatation. Upon initial exposure to hypoxia, CBF is elevated via a greater relative degree of hypoxia compared with hypocapnia. At this point, hypoxia-induced elevations in blood pressure and loss of cerebral autoregulation, stimulation of neuronal pathways, angiogenesis, release of adenosine, endothelium-derived NO and a variety of autocoids and cytokines are additional factors acting to increase CBF. Following 2-3 days, however, the process of ventilatory acclimatization results in a progressive rise in ventilation, which increases PaO2 and reduces PaCO2, collectively acting to attenuate the initial rise in CBF. Other factors acting to lower CBF include elevations in haematocrit, sympathetic nerve activity and local and endothelium-derived vasoconstrictors. Hypoxia-induced alterations of cerebrovascular reactivity, autoregulation and pulmonary vascular tone may also affect CBF. Thus, the extent of change in CBF during exposure to hypoxia is dependent on the balance between the myriad of vasodilators and constrictors derived from the endothelium, neuronal innervations and perfusion pressure. This review examines the extent and mechanisms by which hypoxia regulates CBF. Particular focus will be given to the marked influence of hypoxia associated with exposure to high altitude and chronic lung disease. The associated implications of these hypoxia-induced integrative alterations for the regulation of CBF are discussed, and future avenues for research are proposed.
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Affiliation(s)
- Philip N Ainslie
- Department of Human Kinetics, Faculty of Health and Social Development, University of British Columbia Okanagan, Kelowna V1V 1V7, Canada.
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31
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Zhou H, Saidel GM, LaManna JC. Cerebral Blood Flow Adaptation to Chronic Hypoxia. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 614:371-7. [DOI: 10.1007/978-0-387-74911-2_41] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Roche-Labarbe N, Wallois F, Ponchel E, Kongolo G, Grebe R. Coupled oxygenation oscillation measured by NIRS and intermittent cerebral activation on EEG in premature infants. Neuroimage 2007; 36:718-27. [PMID: 17482837 DOI: 10.1016/j.neuroimage.2007.04.002] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2007] [Revised: 03/27/2007] [Accepted: 04/03/2007] [Indexed: 11/19/2022] Open
Abstract
Electroencephalography of premature neonates shows a physiological discontinuity of electrical activity during quiet sleep. Near infrared spectroscopy (NIRS) shows spontaneous oscillations of hemoglobin oxygenation and volume. Similar oscillations are visible in term neonates and adults, with NIRS and other functional imaging techniques (fMRI, Doppler, etc.), but are generally thought to result from vasomotion and to be a physiological artifact of limited interest. The origin and possible relationship to neuronal activity of the baseline changes in the NIRS signal have not been established. We carried out simultaneous EEG-NIRS recordings on six healthy premature neonates and four premature neonates presenting neurological distress, to determine whether changes in the concentration of cerebral oxy- and deoxy- and total hemoglobin were related to the occurrence of spontaneous bursts of cerebral electric activity. Bursts of electroencephalographic activity in neonates during quiet sleep were found to be coupled to a transient stereotyped hemodynamic response involving a decrease in oxy-hemoglobin concentration, sometimes beginning a few seconds before the onset of electroencephalographic activity, followed by an increase, and then a return to baseline. This pattern could be either part of the baseline oscillations or superimposed changes to this baseline, influencing its shape and phase. The temporal patterns of NIRS parameters present an unique configuration, and tend to be different between our healthy and pathological subjects. Studies of physiological activities and of the effects of intrinsic regulation on the NIRS signal should increase our understanding of these patterns and EEG-NIRS studies should facilitate the integration of NIRS into the set of clinical tools used in neurology.
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Affiliation(s)
- N Roche-Labarbe
- GRAMFC, Faculty of Medicine, 3 rue des louvels, F-80036, Amiens, France.
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Abstract
Exposure to mild hypoxia elicits a characteristic cerebrovascular response in mammals, including humans. Initially, cerebral blood flow (CBF) increases as much as twofold. The blood flow increase is blunted somewhat by a decreasing arterial Pco2 as a result of the hypoxia-induced hyperventilatory response. After a few days, CBF begins to fall back toward baseline levels as the blood oxygen-carrying capacity is increasing due to increasing hemoglobin concentration and packed red cell volume as a result of erythropoietin upregulation. By the end of 2 wk of hypoxic exposure, brain capillary density has increased with resultant decreased intercapillary distances. The relative time courses of these changes suggest that they are adjusted by different control signals and mechanisms. The CBF response appears linked to the blood oxygen-carrying capacity, whereas the hypoxia-induced brain angiogenesis appears to be in response to tissue hypoxia.
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Affiliation(s)
- Kui Xu
- Dept. of Anatomy, School of Medicine, Case Western Reserve Univ., 10900 Euclid Ave., Cleveland, OH 44106-4930, USA
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LaManna JC, Chavez JC, Pichiule P. Structural and functional adaptation to hypoxia in the rat brain. J Exp Biol 2004; 207:3163-9. [PMID: 15299038 DOI: 10.1242/jeb.00976] [Citation(s) in RCA: 149] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
SUMMARY
Chronic exposure to a hypoxic environment leads to structural and functional adaptations in the rat brain. One significant adaptation is a decrease in intercapillary distances through a near doubling of the capillary density, which begins after about 1 week of hypoxic exposure and is completed by 3 weeks. Hypoxic angiogenesis is controlled by activation of downstream genes by Hypoxia Inducible Factor-1 and Angiopoietin-2. The processes that increase capillary density are reversible upon restoration of the ambient oxygen concentration. Capillary regression, which also occurs over a 3-week period, is accomplished through activation of apoptosis. The implication from these observations is that the brain naturally functions in a low, but controlled, oxygen environment. Acute imbalances in oxygen delivery and metabolic demand are addressed through changes in blood flow; persistent imbalances activate mechanisms that adjust capillary density. The mechanisms that control these processes decline with age.
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Affiliation(s)
- Joseph C LaManna
- Departments of Neurology and Anatomy, Case Medical School, Cleveland, OH 44106, USA.
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Glickstein SB, Ilch CP, Golanov EV. Electrical stimulation of the dorsal periaqueductal gray decreases volume of the brain infarction independently of accompanying hypertension and cerebrovasodilation. Brain Res 2003; 994:135-45. [PMID: 14642639 DOI: 10.1016/j.brainres.2003.08.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
We investigated whether selective stimulation of neurons of the sympathoinhibitory ventral periaqueductal gray (VPAG), or sympathoexcitatory dorsal periaqueductal gray (DPAG), differentially modulates CBF and EEG and exerts neuroprotection. Electrical stimulation of either regions of PAG comparably elevated AP and CBF, whereas chemical stimulation with the D,L-homocysteine produced either sympathoinhibition accompanied by decrease in CBF from ventral region or sympathoexcitation accompanied by increase in CBF from dorsal region in nonspinalized rats. The CBF effects evoked from DPAG and VPAG by chemical stimulation were preserved in spinalized rats supporting that the evoked CBF responses result directly from stimulation and are not secondary to AP changes. Stimulation of either region, whether chemical or electrical, synchronized the EEG. To explore whether PAG stimulation might protect the brain against ischemic injury, in other rats the VPAG or DPAG were stimulated for 1 h (50 Hz, 1 s on/1 s off, 75-100 microA) and the middle cerebral artery occluded 72 h later. Stimulation of the DPAG, but not VPAG, significantly reduced infarction volumes relative to sham-stimulated controls as determined 24 h after occlusion. Elevations of AP and CBF did not differ between groups. We conclude: (a). intrinsic neurons of D- and VPAG differentially regulate CBF; (b). neurons of DPAG are neuroprotective independently of changes in CBF and/or AP. The DPAG effect on infarct volume may be related to the central neuroprotective pathway evoked by stimulation of the cerebellar FN.
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Affiliation(s)
- Sara B Glickstein
- Departments of Psychiatry and Neuroscience, Columbia University and New York State Psychiatric Institute, 1051 Riverside Dr, Box #42, New York, NY 10032, USA
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Cobos A, Lima D, Almeida A, Tavares I. Brain afferents to the lateral caudal ventrolateral medulla: a retrograde and anterograde tracing study in the rat. Neuroscience 2003; 120:485-98. [PMID: 12890518 DOI: 10.1016/s0306-4522(03)00209-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The ventrolateral medulla (VLM) modulates autonomic functions, motor reactions and pain responses. The lateralmost part of the caudal VLM (VLMlat) was recently shown to be the VLM area responsible for pain modulation. In the present study, the brain sources of VLMlat afferent fibers were determined by tract-tracing techniques. Following injection of cholera toxin subunit B into the VLMlat, retrogradely labeled neurons in the forebrain occurred at the somatosensory, insular, motor, limbic and infralimbic cortices, and at the central amygdaloid nucleus. Retrogradely labeled neurons in diencephalic regions were observed in the lateral hypothalamus, posterior hypothalamus and paraventricular nucleus. In the brainstem, retrograde labeling occurred at the periaqueductal gray, red nucleus, parabrachial area, nucleus raphe magnus, nucleus tractus solitarii, lateral reticular nucleus and dorsal and ventral medullary reticular formation. In the cerebellum, retrogradely labeled neurons occurred at the lateral nucleus. Following injections of the anterograde tracer biotinylated dextran amine (BDA) into the lateral hypothalamus or paraventricular nucleus, anterogradely labeled fibers were mainly observed in the VLMlat. Injections of BDA into the periaqueductal gray, red nucleus or lateral nucleus of the cerebellum resulted in anterograde labeling in the VLMlat and lateral reticular nucleus. The present study gives an account of the brain regions putatively involved in triggering the modulatory actions elicited from the VLMlat. These include areas committed to somatosensory processing, autonomic control, somatic and visceral motor activity and affective reactions. The findings suggest that the VLMlat may play a major homeostatic role in the integration of nociception with other brain functions.
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Affiliation(s)
- A Cobos
- Institute of Histology and Embryology, Faculdade de Medicina and IBMC, University of Oporto, Alameda Professor Hernâni Monteiro, 4200-319 Porto, Portugal
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Porro CA, Cavazzuti M, Lui F, Giuliani D, Pellegrini M, Baraldi P. Independent time courses of supraspinal nociceptive activity and spinally mediated behavior during tonic pain. Pain 2003; 104:291-301. [PMID: 12855340 DOI: 10.1016/s0304-3959(03)00015-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The behavioral response to acute tissue injury is usually characterized by different phases, but the brain mechanisms underlying changes in pain-related behavior over time are still poorly understood. We aimed to analyze time-dependent changes in metabolic activity levels of 49 forebrain structures in the formalin pain model, using the autoradiographic 2-deoxyglucose method in unanesthetized, freely moving rats. We examined rats during the first phase of pain-related reactions ('early' groups), or during the third recovery phase, 60 min later, when the supraspinally mediated behavioral responses were reduced ('late' group). In the early groups, metabolic rates were bilaterally increased over control values in the periaqueductal gray, zona incerta and in several thalamic nuclei (anteroventral, centrolateral, lateral dorsal, parafascicular, posteromedial, submedius, ventromedial, and ventrobasal complex), as well as in the habenulae and in the parietal, cingulate, antero-dorsal insular, and anterior piriform cortex. A contralateral, somatotopically specific activation was found in the putative hindlimb representation area of the somatosensory cortex. In the late group, noxious-induced activation declined in most structures. However, metabolic rates were higher than controls in the periaqueductal gray and zona incerta and in two other structures not previously active: the prerubral area/field of Forel and the arcuate hypothalamic nucleus. These findings provide a time-dependent functional map of nociceptive and anti-nociceptive forebrain circuits during tonic pain. The parallel decrease in licking behavior and forebrain activity, at times when spinally mediated limb flexion responses were still present, suggests that endogenous antinociceptive systems may differently modulate spinal and supraspinal nociceptive networks following acute tissue injury.
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Affiliation(s)
- Carlo A Porro
- Dipartimento di Scienze e Tecnologie Biomediche, Università di Udine, P.le Kolbe 4, I-33100 Udine, Italy.
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