{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:04:24Z","timestamp":1760241864065,"version":"build-2065373602"},"reference-count":23,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2018,9,26]],"date-time":"2018-09-26T00:00:00Z","timestamp":1537920000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004359","name":"Vetenskapsr\u00e5det","doi-asserted-by":"publisher","award":["2016-04220"],"award-info":[{"award-number":["2016-04220"]}],"id":[{"id":"10.13039\/501100004359","id-type":"DOI","asserted-by":"publisher"}]},{"name":"German Research Foundation","award":["CRC 1213"],"award-info":[{"award-number":["CRC 1213"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Acute hypoxia changes the redox-state of pulmonary arterial smooth muscle cells (PASMCs). This might influence the activity of redox-sensitive voltage-gated K+-channels (Kv-channels) whose inhibition initiates hypoxic pulmonary vasoconstriction (HPV). However, the molecular mechanism of how hypoxia\u2014or the subsequent change in the cellular redox-state\u2014inhibits Kv-channels remains elusive. For this purpose, a new multifunctional gas-tight microfluidic system was developed enabling simultaneous single-cell Raman spectroscopic studies (to sense the redox-state under normoxic\/hypoxic conditions) and patch-clamp experiments (to study the Kv-channel activity). The performance of the system was tested by optically recording the O2-content and taking Raman spectra on murine PASMCs under normoxic\/hypoxic conditions or in the presence of H2O2. Oxygen sensing showed that hypoxic levels in the gas-tight microfluidic system were achieved faster, more stable and significantly lower compared to a conventional open system (1.6 \u00b1 0.2%, respectively 6.7 \u00b1 0.7%, n = 6, p &lt; 0.001). Raman spectra revealed that the redistribution of biomarkers (cytochromes, FeS, myoglobin and NADH) under hypoxic\/normoxic conditions were improved in the gas-tight microfluidic system (p-values from 0.00% to 16.30%) compared to the open system (p-value from 0.01% to 98.42%). In conclusion, the new redox sensor holds promise for future experiments that may elucidate the role of Kv-channels during HPV.<\/jats:p>","DOI":"10.3390\/s18103238","type":"journal-article","created":{"date-parts":[[2018,9,26]],"date-time":"2018-09-26T10:39:58Z","timestamp":1537958398000},"page":"3238","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Development of a Gas-Tight Microfluidic System for Raman Sensing of Single Pulmonary Arterial Smooth Muscle Cells Under Normoxic\/Hypoxic Conditions"],"prefix":"10.3390","volume":"18","author":[{"given":"Fenja","family":"Knoepp","sequence":"first","affiliation":[{"name":"Excellence-Cluster Cardio-Pulmonary System (ECCPS), Universities of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Justus-Liebig University Giessen, D-35392 Giessen, Germany"}]},{"given":"Joel","family":"Wahl","sequence":"additional","affiliation":[{"name":"Department of Engineering Sciences and Mathematics, Lule\u00e5 University of Technology, SE-97187 Lule\u00e5, Sweden"}]},{"given":"Anders","family":"Andersson","sequence":"additional","affiliation":[{"name":"Department of Engineering Sciences and Mathematics, Lule\u00e5 University of Technology, SE-97187 Lule\u00e5, Sweden"}]},{"given":"Johan","family":"Borg","sequence":"additional","affiliation":[{"name":"CMS, Imperial College, London SW7 2AZ, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2675-3871","authenticated-orcid":false,"given":"Norbert","family":"Weissmann","sequence":"additional","affiliation":[{"name":"Excellence-Cluster Cardio-Pulmonary System (ECCPS), Universities of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Justus-Liebig University Giessen, D-35392 Giessen, Germany"}]},{"given":"Kerstin","family":"Ramser","sequence":"additional","affiliation":[{"name":"Department of Engineering Sciences and Mathematics, Lule\u00e5 University of Technology, SE-97187 Lule\u00e5, Sweden"}]}],"member":"1968","published-online":{"date-parts":[[2018,9,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"367","DOI":"10.1152\/physrev.00041.2010","article-title":"Hypoxic Pulmonary Vasoconstriction","volume":"92","author":"Sylvester","year":"2012","journal-title":"Physiol. 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