In vitro intermittent hypoxia: challenges for creating hypoxia in cell culture

• Published in: Respiratory physiology & neurobiology 2003-07, Vol.136 (2), p.131-139
• Main Authors: Baumgardner, James E., Otto, Cynthia M.
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Cell Culture Techniques - methods; Cell Hypoxia; Cell metabolism, cell oxidation; Cell physiology; Cell, culture, intermittent hypoxia; Cells, Cultured; Diffusion Chambers, Culture - methods; Disease, sleep apnea; Equipment Design; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation; Hypercapnia; Hypoxia, intermittent, sleep apnea; Interferon-gamma - metabolism; Lipopolysaccharides - metabolism; Methods, cell culture, hypoxia; Mice; Models, Biological; Molecular and cellular biology; Nitric Oxide Synthase - genetics; Nitric Oxide Synthase - metabolism; Nitric Oxide Synthase Type II; Oxygen - analysis; Oxygen - metabolism; Oxygen Consumption; Partial Pressure; Reverse Transcriptase Polymerase Chain Reaction - methods; RNA, Messenger - biosynthesis; Sleep, apnea; Time Factors
• ISSN: 1569-9048; 1878-1519
• DOI: 10.1016/S1569-9048(03)00077-6

Intermittent hypoxia has been implicated in morbidities associated with sleep apnea, and may be a novel cellular signal for inflammation [J. Appl. Physiol. 90 (2001) 1986]. Standard cell culture has two major limitations for studying the effects of steady-state P O 2 and intermittent hypoxia. First, convective mixing in the culture media can be variable, making precise control of cellular P O 2 difficult. Second, diffusion of oxygen through the culture media slows changes in cellular P O 2 after rapid changes in the gas phase P O 2 . Our estimates of diffusional transients for standard cell culture suggest significant restrictions in the ability to cycle P O 2 at frequencies relevant to intermittent hypoxia. We present a novel system for forced convection cell culture with adherent cells inside capillary tubing. Steady state cellular P O 2 is regulated to an accuracy of approximately 1 Torr. The response time for cycling of P O 2 is less than 1.6 sec. This system is ideally suited for studies of intermittent hypoxia in adherent cells.