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Bachmann M, Basoalto R, Díaz O, Bruhn A, Bugedo G, Retamal J. Prone position improves ventilation-perfusion mismatch in patients with severe acute respiratory distress syndrome. Med Intensiva 2023; 47:175-178. [PMID: 36855736 PMCID: PMC9950759 DOI: 10.1016/j.medin.2022.06.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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De Logu F, Nassini R, Hegron A, Landini L, Jensen DD, Latorre R, Ding J, Marini M, Souza Monteiro de Araujo D, Ramírez-Garcia P, Whittaker M, Retamal J, Titiz M, Innocenti A, Davis TP, Veldhuis N, Schmidt BL, Bunnett NW, Geppetti P. Schwann cell endosome CGRP signals elicit periorbital mechanical allodynia in mice. Nat Commun 2022; 13:646. [PMID: 35115501 PMCID: PMC8813987 DOI: 10.1038/s41467-022-28204-z] [Citation(s) in RCA: 50] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 01/14/2022] [Indexed: 01/07/2023] Open
Abstract
Efficacy of monoclonal antibodies against calcitonin gene-related peptide (CGRP) or its receptor (calcitonin receptor-like receptor/receptor activity modifying protein-1, CLR/RAMP1) implicates peripherally-released CGRP in migraine pain. However, the site and mechanism of CGRP-evoked peripheral pain remain unclear. By cell-selective RAMP1 gene deletion, we reveal that CGRP released from mouse cutaneous trigeminal fibers targets CLR/RAMP1 on surrounding Schwann cells to evoke periorbital mechanical allodynia. CLR/RAMP1 activation in human and mouse Schwann cells generates long-lasting signals from endosomes that evoke cAMP-dependent formation of NO. NO, by gating Schwann cell transient receptor potential ankyrin 1 (TRPA1), releases ROS, which in a feed-forward manner sustain allodynia via nociceptor TRPA1. When encapsulated into nanoparticles that release cargo in acidified endosomes, a CLR/RAMP1 antagonist provides superior inhibition of CGRP signaling and allodynia in mice. Our data suggest that the CGRP-mediated neuronal/Schwann cell pathway mediates allodynia associated with neurogenic inflammation, contributing to the algesic action of CGRP in mice.
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Affiliation(s)
- Francesco De Logu
- Department of Health Sciences, Clinical Pharmacology and Oncology Section, University of Florence, Florence, 50139, Italy
| | - Romina Nassini
- Department of Health Sciences, Clinical Pharmacology and Oncology Section, University of Florence, Florence, 50139, Italy
- Headache Center, Careggi University Hospital, Florence, 50139, Italy
| | - Alan Hegron
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, NY, 10010, USA
| | - Lorenzo Landini
- Department of Health Sciences, Clinical Pharmacology and Oncology Section, University of Florence, Florence, 50139, Italy
| | - Dane D Jensen
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, NY, 10010, USA
- Bluestone Center for Clinical Research, New York University College of Dentistry, New York, NY, 10010, USA
| | - Rocco Latorre
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, NY, 10010, USA
| | - Julia Ding
- Department of Anesthesiology, Columbia University, New York, NY, 10010, USA
| | - Matilde Marini
- Department of Health Sciences, Clinical Pharmacology and Oncology Section, University of Florence, Florence, 50139, Italy
| | | | - Paulina Ramírez-Garcia
- Drug Discovery Biology Theme and Australian Research Council Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
| | - Michael Whittaker
- Drug Discovery Biology Theme and Australian Research Council Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
| | - Jeffri Retamal
- Drug Discovery Biology Theme and Australian Research Council Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
| | - Mustafa Titiz
- Department of Health Sciences, Clinical Pharmacology and Oncology Section, University of Florence, Florence, 50139, Italy
| | - Alessandro Innocenti
- Plastic and Reconstructive Microsurgery - Careggi University Hospital, Florence, 50139, Italy
| | - Thomas P Davis
- Drug Discovery Biology Theme and Australian Research Council Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Nicholas Veldhuis
- Drug Discovery Biology Theme and Australian Research Council Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
| | - Brian L Schmidt
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, NY, 10010, USA
- Bluestone Center for Clinical Research, New York University College of Dentistry, New York, NY, 10010, USA
- Department of Neuroscience and Physiology and Neuroscience Institute, School of Medicine, New York University, New York, NY, 10010, USA
| | - Nigel W Bunnett
- Department of Molecular Pathobiology, College of Dentistry, New York University, New York, NY, 10010, USA.
- Department of Neuroscience and Physiology and Neuroscience Institute, School of Medicine, New York University, New York, NY, 10010, USA.
| | - Pierangelo Geppetti
- Department of Health Sciences, Clinical Pharmacology and Oncology Section, University of Florence, Florence, 50139, Italy.
- Headache Center, Careggi University Hospital, Florence, 50139, Italy.
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Araos J, Boullhesen-Williams T, Perez A, Retamal J, Martin-Flores M, Gleed R, Staffieri F, Hurtado D. Regional distribution of static lung strain induced by positive-end expiratory pressure (PEEP) in healthy, dorsally recumbent, anesthetized and mechanically ventilated dogs. Vet Anaesth Analg 2020. [DOI: 10.1016/j.vaa.2020.07.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Araos J, Boullhesen-Williams T, Retamal J, Perez A, Martin-Flores M, Gleed R, Staffieri F, Hurtado D. Regional maps of volumetric lung strain in healthy anesthetized dogs ventilated with varying tidal volumes and positive end-expiratory pressure (PEEP). Vet Anaesth Analg 2020. [DOI: 10.1016/j.vaa.2020.07.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Retamal J, Reyes A, Ramirez P, Bravo D, Hernandez A, Pelissier T, Villanueva L, Constandil L. Burst-Like Subcutaneous Electrical Stimulation Induces BDNF-Mediated, Cyclotraxin B-Sensitive Central Sensitization in Rat Spinal Cord. Front Pharmacol 2018; 9:1143. [PMID: 30364099 PMCID: PMC6191473 DOI: 10.3389/fphar.2018.01143] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 09/21/2018] [Indexed: 11/18/2022] Open
Abstract
Intrathecal administration of brain derived neurotrophic factor (BDNF) induces long-term potentiation (LTP) and generates long-lasting central sensitization in spinal cord thus mimicking chronic pain, but the relevance of these observations to chronic pain mechanisms is uncertain. Since C-fiber activation by a high-frequency subcutaneous electrical stimulation (SES) protocol causes spinal release of BDNF and induces spinal cord LTP, we propose that application of such protocol would be a sufficient condition for generating long-lasting BDNF-mediated central sensitization. Results showed that application of burst-like SES to rat toes produced (i) rapid induction of hyperalgesia that lasted for more than 3 weeks, (ii) early increase of C-reflex activity followed by increased wind-up scores lasting for more than 1 week, and (iii) early increase followed by late decrease in BDNF protein levels and phosphorylated TrkB that lasted for more than 1 week. These changes were prevented by the TrkB antagonist cyclotraxin-B administered shortly before SES, while hyperalgesia was reversed by cyclotraxin-B administered 3 days after SES. Results suggest that mechanisms underlying central sensitization first involve BDNF release of probably neuronal origin, followed by brief increased expression of likely glial BDNF and pTrkB that could switch early phase sensitization into late one.
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Affiliation(s)
- Jeffri Retamal
- Laboratory of Neurobiology, Department of Biology, Faculty of Chemistry and Biology, University of Santiago de Chile, Santiago, Chile.,Center for the Development of Nanoscience and Nanotechnology (CEDENNA), Santiago, Chile
| | - Andrea Reyes
- Laboratory of Neurobiology, Department of Biology, Faculty of Chemistry and Biology, University of Santiago de Chile, Santiago, Chile
| | - Paulina Ramirez
- Laboratory of Neurobiology, Department of Biology, Faculty of Chemistry and Biology, University of Santiago de Chile, Santiago, Chile.,Center for the Development of Nanoscience and Nanotechnology (CEDENNA), Santiago, Chile
| | - David Bravo
- Laboratory of Neurobiology, Department of Biology, Faculty of Chemistry and Biology, University of Santiago de Chile, Santiago, Chile.,Center for the Development of Nanoscience and Nanotechnology (CEDENNA), Santiago, Chile
| | - Alejandro Hernandez
- Laboratory of Neurobiology, Department of Biology, Faculty of Chemistry and Biology, University of Santiago de Chile, Santiago, Chile
| | - Teresa Pelissier
- Program of Molecular and Clinical Pharmacology, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Luis Villanueva
- Centre de Psychiatrie et Neurosciences, INSERM UMR 894, Paris, France
| | - Luis Constandil
- Laboratory of Neurobiology, Department of Biology, Faculty of Chemistry and Biology, University of Santiago de Chile, Santiago, Chile.,Center for the Development of Nanoscience and Nanotechnology (CEDENNA), Santiago, Chile
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Ili C, Retamal J, Lopez J, Riquelme I, Bellolio E, Viscarra T, Zanella L, Abanto M, Buchegger K, Brebi P. PO-183 Identification of differentially hypomethylated genes associated to metastasis behaviour in colorectal cancer. ESMO Open 2018. [DOI: 10.1136/esmoopen-2018-eacr25.222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Retamal J, Borges JB, Bruhn A, Feinstein R, Hedenstierna G, Suarez-Sipmann F, Larsson A. Open lung approach ventilation abolishes the negative effects of respiratory rate in experimental lung injury. Acta Anaesthesiol Scand 2016; 60:1131-41. [PMID: 27110871 DOI: 10.1111/aas.12735] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 03/09/2016] [Accepted: 03/11/2016] [Indexed: 01/05/2023]
Abstract
BACKGROUND We recently reported that a high respiratory rate was associated with less inflammation than a low respiratory rate, but caused more pulmonary edema in a model of ARDS when an ARDSNet ventilatory strategy was used. We hypothesized that an open lung approach (OLA) strategy would neutralize the independent effects of respiratory rate on lung inflammation and edema. This hypothesis was tested in an ARDS model using two clinically relevant respiratory rates during OLA strategy. METHODS Twelve piglets were subjected to an experimental model of ARDS and randomized into two groups: LRR (20 breaths/min) and HRR (40 breaths/min). They were mechanically ventilated for 6 h according to an OLA strategy. We assessed respiratory mechanics, hemodynamics, and extravascular lung water (EVLW). At the end of the experiment, wet/dry ratio, regional histology, and cytokines were evaluated. RESULTS After the ARDS model was established, Cdyn,rs decreased from 21 ± 3.3 to 9.0 ± 1.8 ml/cmH2 O (P < 0.0001). After the lung recruitment maneuver, Cdyn,rs increased to the pre-injury value. During OLA ventilation, no differences in respiratory mechanics, hemodynamics, or EVLW were observed between groups. Wet/dry ratio and histological scores were not different between groups. Cytokine quantification was similar and showed a homogeneous distribution throughout the lung in both groups. CONCLUSION Contrary to previous findings with the ARDSNet strategy, respiratory rate did not influence lung inflammatory response or pulmonary edema during OLA ventilation in experimental ARDS. This indicates that changing the respiratory rate when OLA ventilation is used will not exacerbate lung injury.
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Affiliation(s)
- J. Retamal
- Hedenstierna Laboratory; Department of Surgical Sciences; Section of Anaesthesiology & Critical Care; Uppsala University; Uppsala Sweden
- Departamento de Medicina Intensiva; Pontificia Universidad Católica de Chile; Santiago Chile
| | - J. B. Borges
- Hedenstierna Laboratory; Department of Surgical Sciences; Section of Anaesthesiology & Critical Care; Uppsala University; Uppsala Sweden
- Cardio-Pulmonary Department; Pulmonary Divison; Heart Institute (Incor); University of São Paulo; São Paulo Brazil
| | - A. Bruhn
- Departamento de Medicina Intensiva; Pontificia Universidad Católica de Chile; Santiago Chile
| | - R. Feinstein
- Department of Pathology and Wildlife Diseases; National Veterinary Institute; Uppsala Sweden
| | - G. Hedenstierna
- Department of Medical Science; Clinical Physiology; Uppsala University Hospital; Uppsala Sweden
| | - F. Suarez-Sipmann
- Hedenstierna Laboratory; Department of Surgical Sciences; Section of Anaesthesiology & Critical Care; Uppsala University; Uppsala Sweden
| | - A. Larsson
- Hedenstierna Laboratory; Department of Surgical Sciences; Section of Anaesthesiology & Critical Care; Uppsala University; Uppsala Sweden
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Retamal J, Borges JB, Bruhn A, Cao X, Feinstein R, Hedenstierna G, Johansson S, Suarez-Sipmann F, Larsson A. High respiratory rate is associated with early reduction of lung edema clearance in an experimental model of ARDS. Acta Anaesthesiol Scand 2016; 60:79-92. [PMID: 26256848 DOI: 10.1111/aas.12596] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 07/08/2015] [Accepted: 07/13/2015] [Indexed: 12/21/2022]
Abstract
BACKGROUND The independent impact of respiratory rate on ventilator-induced lung injury has not been fully elucidated. The aim of this study was to investigate the effects of two clinically relevant respiratory rates on early ventilator-induced lung injury evolution and lung edema during the protective ARDSNet strategy. We hypothesized that the use of a higher respiratory rate during a protective ARDSNet ventilation strategy increases lung inflammation and, in addition, lung edema associated to strain-induced activation of transforming growth factor beta (TGF-β) in the lung epithelium. METHODS Twelve healthy piglets were submitted to a two-hit lung injury model and randomized into two groups: LRR (20 breaths/min) and HRR (40 breaths/min). They were mechanically ventilated during 6 h according to the ARDSNet strategy. We assessed respiratory mechanics, hemodynamics, and extravascular lung water (EVLW). At the end of the experiment, the lungs were excised and wet/dry ratio, TGF-β pathway markers, regional histology, and cytokines were evaluated. RESULTS No differences in oxygenation, PaCO2 levels, systemic and pulmonary arterial pressures were observed during the study. Respiratory system compliance and mean airway pressure were lower in LRR group. A decrease in EVLW over time occurred only in the LRR group (P < 0.05). Wet/dry ratio was higher in the HRR group (P < 0.05), as well as TGF-β pathway activation. Histological findings suggestive of inflammation and inflammatory tissue cytokines were higher in LRR. CONCLUSION HRR was associated with more pulmonary edema and higher activation of the TGF-β pathway. In contrast with our hypothesis, HRR was associated with less lung inflammation.
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Affiliation(s)
- J. Retamal
- Hedenstierna Laboratory; Department of Surgical Sciences; Section of Anaesthesiology & Critical Care; Uppsala University; Uppsala Sweden
- Departamento de Medicina Intensiva; Pontificia Universidad Cat ó lica de Chile; Santiago Chile
| | - J. B. Borges
- Hedenstierna Laboratory; Department of Surgical Sciences; Section of Anaesthesiology & Critical Care; Uppsala University; Uppsala Sweden
- Cardio-Pulmonary Department; Pulmonary Divison; Heart Institute (Incor); University of São Paulo; São Paulo Brazil
| | - A. Bruhn
- Departamento de Medicina Intensiva; Pontificia Universidad Cat ó lica de Chile; Santiago Chile
| | - X. Cao
- Department of Medical Biochemistry and Microbiology; Uppsala University; Uppsala Sweden
| | - R. Feinstein
- Department of Pathology and Wildlife Diseases; National Veterinary Institute; Uppsala Sweden
| | - G. Hedenstierna
- Department of Medical Science, Clinical Physiology; Uppsala University Hospital; Uppsala Sweden
| | - S. Johansson
- Department of Medical Biochemistry and Microbiology; Uppsala University; Uppsala Sweden
| | - F. Suarez-Sipmann
- Hedenstierna Laboratory; Department of Surgical Sciences; Section of Anaesthesiology & Critical Care; Uppsala University; Uppsala Sweden
| | - A. Larsson
- Hedenstierna Laboratory; Department of Surgical Sciences; Section of Anaesthesiology & Critical Care; Uppsala University; Uppsala Sweden
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Retamal J, Bugedo G, Larsson A, Bruhn A. High PEEP levels are associated with overdistension and tidal recruitment/derecruitment in ARDS patients. Acta Anaesthesiol Scand 2015; 59:1161-9. [PMID: 26061818 DOI: 10.1111/aas.12563] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 04/28/2015] [Accepted: 04/30/2015] [Indexed: 01/14/2023]
Abstract
BACKGROUND Positive end-expiratory pressure (PEEP) improves gas exchange and respiratory mechanics, and it may decrease tissue injury and inflammation. The mechanisms of this protective effect are not fully elucidated. Our aim was to determine the intrinsic effects of moderate and higher levels of PEEP on tidal recruitment/derecruitment, hyperinflation, and lung mechanics, in patients with acute respiratory distress syndrome (ARDS). METHODS Nine patients with ARDS of mainly pulmonary origin were ventilated sequential and randomly using two levels of PEEP: 9 and 15 cmH2 O, and studied with dynamic computed tomography at a fix transversal lung region. Tidal recruitment/derecruitment and hyperinflation were determined as non-aerated tissue and hyperinflated tissue variation between inspiration and expiration, expressed as percentage of total weight. We also assessed the maximal amount of non-aerated and hyperinflated tissue weight. RESULTS PEEP 15 cmH2 O was associated with decrease in non-aerated tissue in all the patients (P < 0.01). However, PEEP 15 cmH2 O did not decrease tidal recruitment/derecruitment compared to PEEP 9 cmH2 O (P = 1). In addition, PEEP 15 cmH2 O markedly increased maximal hyperinflation (P < 0.01) and tidal hyperinflation (P < 0.05). Lung compliance decreased with PEEP 15 cmH2 O (P < 0.001). CONCLUSION In this series of patients with ARDS of mainly pulmonary origin, application of high levels of PEEP did not decrease tidal recruitment/derecruitment, but instead consistently increased tidal and maximal hyperinflation.
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Affiliation(s)
- J. Retamal
- Facultad de Medicina; Departamento de Medicina Intensiva; Pontificia Universidad Católica de Chile; Santiago Chile
- Hedenstierna Laboratory; Surgical Science Department; Uppsala University; Uppsala Sweden
| | - G. Bugedo
- Facultad de Medicina; Departamento de Medicina Intensiva; Pontificia Universidad Católica de Chile; Santiago Chile
| | - A. Larsson
- Hedenstierna Laboratory; Surgical Science Department; Uppsala University; Uppsala Sweden
| | - A. Bruhn
- Facultad de Medicina; Departamento de Medicina Intensiva; Pontificia Universidad Católica de Chile; Santiago Chile
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Retamal J, Borges JB, Suarez-Sipmann F, Bruhn A, Hedenstierna G, Larsson A. 0893. High respiratory rate favors pulmonary edema in an experimental model of acute lung injury. Intensive Care Med Exp 2014. [PMCID: PMC4797579 DOI: 10.1186/2197-425x-2-s1-o19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Bravo D, Ibarra P, Retamal J, Pelissier T, Laurido C, Hernandez A, Constandil L. Pannexin 1: a novel participant in neuropathic pain signaling in the rat spinal cord. Pain 2014; 155:2108-15. [PMID: 25102401 DOI: 10.1016/j.pain.2014.07.024] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 06/30/2014] [Accepted: 07/29/2014] [Indexed: 01/28/2023]
Abstract
Pannexin 1 (panx1) is a large-pore membrane channel expressed in many tissues of mammals, including neurons and glial cells. Panx1 channels are highly permeable to calcium and adenosine triphosphatase (ATP); on the other hand, they can be opened by ATP and glutamate, two crucial molecules for acute and chronic pain signaling in the spinal cord dorsal horn, thus suggesting that panx1 could be a key component for the generation of central sensitization during persistent pain. In this study, we examined the effect of three panx1 blockers, namely, 10panx peptide, carbenoxolone, and probenecid, on C-reflex wind-up activity and mechanical nociceptive behavior in a spared nerve injury neuropathic rat model involving sural nerve transection. In addition, the expression of panx1 protein in the dorsal horn of the ipsilateral lumbar spinal cord was measured in sural nerve-transected and sham-operated control rats. Sural nerve transection resulted in a lower threshold for C-reflex activation by electric stimulation of the injured hindpaw, together with persistent mechanical hypersensitivity to pressure stimuli applied to the paw. Intrathecal administration of the panx1 blockers significantly depressed the spinal C-reflex wind-up activity in both neuropathic and sham control rats, and decreased mechanical hyperalgesia in neuropathic rats without affecting the nociceptive threshold in sham animals. Western blotting showed that panx1 was similarly expressed in the dorsal horn of lumbar spinal cord from neuropathic and sham rats. The present results constitute the first evidence that panx1 channels play a significant role in the mechanisms underlying central sensitization in neuropathic pain.
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Affiliation(s)
- David Bravo
- Laboratory of Neurobiology, Department of Biology, Faculty of Chemistry and Biology, University of Santiago of Chile, Santiago, Chile
| | - Paula Ibarra
- Laboratory of Neurobiology, Department of Biology, Faculty of Chemistry and Biology, University of Santiago of Chile, Santiago, Chile
| | - Jeffri Retamal
- Laboratory of Neurobiology, Department of Biology, Faculty of Chemistry and Biology, University of Santiago of Chile, Santiago, Chile
| | - Teresa Pelissier
- Program of Molecular and Clinical Pharmacology, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Claudio Laurido
- Laboratory of Neurobiology, Department of Biology, Faculty of Chemistry and Biology, University of Santiago of Chile, Santiago, Chile
| | - Alejandro Hernandez
- Laboratory of Neurobiology, Department of Biology, Faculty of Chemistry and Biology, University of Santiago of Chile, Santiago, Chile
| | - Luis Constandil
- Laboratory of Neurobiology, Department of Biology, Faculty of Chemistry and Biology, University of Santiago of Chile, Santiago, Chile.
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Bruhn A, Bugedo D, Riquelme F, Varas J, Retamal J, Besa C, Cabrera C, Bugedo G. Tidal volume is a major determinant of cyclic recruitment-derecruitment in acute respiratory distress syndrome. Minerva Anestesiol 2011; 77:418-426. [PMID: 21483386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
BACKGROUND Overdistension and cyclic recruitment-derecruitment contribute to ventilator-induced lung injury. High tidal volumes are thought to increase mortality mainly by inducing overdistension. However, experimental evidence suggests that tidal volume (VT) may also influence cyclic recruitment-derecruitment. Our main goal was to determine whether high tidal volumes increase cyclic recruitment-derecruitment in acute respiratory distress syndrome (ARDS) patients, as measured by dynamic computed tomography (CT). METHODS We studied 9 ARDS patients with diffuse attenuations on CT who underwent a protocol including 2 ventilatory modes: (a) VT 6 mL/kg, respiratory rate 30/min, PEEP 9 cmH2O, (b) VT 12 mL/kg, respiratory rate 15/min, PEEP 9 cmH2O. A dynamic computed tomography of 8 seconds on a fixed transverse region was performed during each ventilator mode. Cyclic recruitment-derecruitment was determined as non-aerated tissue variation between inspiration and expiration and was expressed as % of lung tissue weight. RESULTS VT 12 mL/kg exhibited less non-aerated tissue at expiration compared to VT 6 ml/kg (40.15 [35.94-56.00] and 45.31 [37.95-59.32], respectively, P<0.05). However, VT 12 ml/kg increased cyclic recruitment-derecruitment compared to VT 6 mL/kg (7.32 [6.58-9.29] mL/kg vs. 4.51 [3.42-5.75] mL/kg, P<0.01). Tidal hyperinflation was also larger at VT 12 mL/kg (0.55 [0.27-2.24] vs. 0.24 [0.18-0.83], P<0.01). CONCLUSION High tidal volume is a major determinant of cyclic recruitment-derecruitment in ARDS patients with diffuse attenuations.
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Affiliation(s)
- A Bruhn
- Department of Intensive Medicine, Pontifical Catholic University of Chile, Santiago, Chile.
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Retamal J, Libuy J, Jimenez M, Delgado M, Besa C, Bugedo G, Bruhn A. Decreasing tidal volume from 6 to 4 ml/kg: feasibility and effects on repeated opening and closing. Crit Care 2010. [PMCID: PMC2934053 DOI: 10.1186/cc8420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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