{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T15:39:13Z","timestamp":1785425953540,"version":"3.56.0"},"reference-count":37,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T00:00:00Z","timestamp":1783555200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Spanish Ministry of Science, Innovation and Universities","award":["PID2023-146070OB-I00"],"award-info":[{"award-number":["PID2023-146070OB-I00"]}]},{"name":"Spanish Ministry of Science, Innovation and Universities","award":["PID2023-147668OB-I00"],"award-info":[{"award-number":["PID2023-147668OB-I00"]}]},{"name":"Spanish Ministry of Science, Innovation and Universities","award":["MCIU\/AEI \/10.13039\/501100011033"],"award-info":[{"award-number":["MCIU\/AEI \/10.13039\/501100011033"]}]},{"award":["PID2023-146070OB-I00"],"award-info":[{"award-number":["PID2023-146070OB-I00"]}],"id":[{"id":"https:\/\/ror.org\/05r0vyz12","id-type":"ROR","asserted-by":"publisher"}]},{"award":["PID2023-147668OB-I00"],"award-info":[{"award-number":["PID2023-147668OB-I00"]}],"id":[{"id":"https:\/\/ror.org\/05r0vyz12","id-type":"ROR","asserted-by":"publisher"}]},{"award":["MCIU\/AEI \/10.13039\/501100011033"],"award-info":[{"award-number":["MCIU\/AEI \/10.13039\/501100011033"]}],"id":[{"id":"https:\/\/ror.org\/05r0vyz12","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Life"],"abstract":"<jats:p>Very prevalent respiratory and cardiovascular diseases result in chronic hypoxia, promoting metabolic, kidney, heart, and other malignant diseases. Hypoxia research employs animal models based on chronically breathing hypoxic air (O2 &lt; 21%), usually by injecting N2 into the animal\u2019s chamber. However, continuous high-flow N2 supply is available only in limited facilities, reducing the capability for hypoxia research to be widely conducted. Here, we describe an optimized setting for subjecting rodents to chronic normobaric hypoxia by requiring minimal N2 supply. The primary aim of this study was the technical development and optimization of a system for chronic normobaric hypoxia exposure rather than testing a specific biological hypothesis The setting is based on providing the O2 consumed by the animals and eliminating the exhaled CO2 and water vapor. O2, CO2, temperature, and humidity in the hypoxic chamber are controlled by an Arduino-based unit activating a pump that introduces room air to restore the metabolized O2. Another pump continuously recirculates the chamber air through a Peltier-based dryer and CO2-absorbing soda lime. To correct any deviation in the actual value of hypoxia within the chamber, the control unit allows the injection of N2 into the chamber from a gas source. The setting performance was successfully tested in vivo when subjecting mice to 11%\u2013O2 chronic hypoxia. This device, requiring a low N2 supply, may facilitate in vivo experimental research on hypoxia-related diseases.<\/jats:p>","DOI":"10.3390\/life16071140","type":"journal-article","created":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T08:50:56Z","timestamp":1783587056000},"page":"1140","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Optimized Open-Source Setting for Subjecting Rodents to Chronic Normobaric Hypoxia in Facilities with Minimal Nitrogen Supply"],"prefix":"10.3390","volume":"16","author":[{"given":"Jorge","family":"Otero","sequence":"first","affiliation":[{"name":"Unit of Biophysics and Bioengineering, School of Medicine and Health Sciences, University of Barcelona, Casanova 143, 08036 Barcelona, Spain"},{"name":"CIBER of Respiratory Diseases (CIBERES), Monforte de Lemos 3\u20135, 28029 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miguel A.","family":"Rodr\u00edguez-L\u00e1zaro","sequence":"additional","affiliation":[{"name":"Unit of Biophysics and Bioengineering, School of Medicine and Health Sciences, University of Barcelona, Casanova 143, 08036 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raffaella","family":"Salama","sequence":"additional","affiliation":[{"name":"Unit of Biophysics and Bioengineering, School of Medicine and Health Sciences, University of Barcelona, Casanova 143, 08036 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9489-1339","authenticated-orcid":false,"given":"Daniel","family":"Mbanze","sequence":"additional","affiliation":[{"name":"Unit of Biophysics and Bioengineering, School of Medicine and Health Sciences, University of Barcelona, Casanova 143, 08036 Barcelona, Spain"},{"name":"Faculdade de Engenharias e Tecnologias, Universidade Save, Estrada Nacional N\/C. Agostinho Neto Nhaguiviga, Maxixe, Inhambane, Mozambique"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1212-0574","authenticated-orcid":false,"given":"Gorka","family":"Solana","sequence":"additional","affiliation":[{"name":"Faculdade de Engenharias e Tecnologias, Universidade Save, Estrada Nacional N\/C. Agostinho Neto Nhaguiviga, Maxixe, Inhambane, Mozambique"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vicent","family":"Mu\u00f1oz-Va\u00f1o","sequence":"additional","affiliation":[{"name":"Research Group on Neuromuscular and Mitochondrial Diseases, Vall d\u2019Hebron Research Institute, Universitat Aut\u00f2noma de Barcelona, Passeig Vall d\u2019Hebron 119\u2013129, 08035 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yolanda","family":"C\u00e1mara","sequence":"additional","affiliation":[{"name":"Research Group on Neuromuscular and Mitochondrial Diseases, Vall d\u2019Hebron Research Institute, Universitat Aut\u00f2noma de Barcelona, Passeig Vall d\u2019Hebron 119\u2013129, 08035 Barcelona, Spain"},{"name":"CIBER of Rare Diseases (CIBERER), Monforte de Lemos 3\u20135, 28029 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1998-9379","authenticated-orcid":false,"given":"Isaac","family":"Almendros","sequence":"additional","affiliation":[{"name":"Unit of Biophysics and Bioengineering, School of Medicine and Health Sciences, University of Barcelona, Casanova 143, 08036 Barcelona, Spain"},{"name":"CIBER of Respiratory Diseases (CIBERES), Monforte de Lemos 3\u20135, 28029 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9084-7824","authenticated-orcid":false,"given":"Ramon","family":"Farr\u00e9","sequence":"additional","affiliation":[{"name":"Unit of Biophysics and Bioengineering, School of Medicine and Health Sciences, University of Barcelona, Casanova 143, 08036 Barcelona, Spain"},{"name":"CIBER of Respiratory Diseases (CIBERES), Monforte de Lemos 3\u20135, 28029 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,9]]},"reference":[{"key":"ref_1","unstructured":"GBD Chronic Respiratory Disease Collaborators (2020). 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