A novel system including an N2 gas generator and an air compressor for inducing intermittent or chronic hypoxia

Hisashi Nagai; Hirotsugu Tsuchimochi; Ken‑ichi Yoshida; Mikiyasu Shirai; Ichiro Kuwahira

Hisashi Nagai Department of Forensic Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Japan
Hirotsugu Tsuchimochi Department of Cardiac Physiology, National Cerebral and Cardiovascular Center, Osaka, Japan
Ken‑ichi Yoshida Department of Forensic Medicine, Tokyo Medical University, Tokyo, Japan
Mikiyasu Shirai Department of Cardiac Physiology, National Cerebral and Cardiovascular Center, Osaka, Japan
Ichiro Kuwahira Department of Respiratory Medicine, Tokai University Tokyo Hospital, Tokyo, Japan

Keywords: Chronic hypoxia, Hypoxia‑inducing systems, Intermittent hypoxia

Abstract

Background and Aim: Animals that have been exposed to intermittent or chronic hypoxia (CH) for long periods are often used for basic research into various pulmonary and cardiac conditions. In standard hypoxia‑inducing systems, gas cylinders are used to supply the hypoxic gas. Thus, it is necessary to exchange the cylinders very often. Methods: To resolve this difficulty, we have developed a system including an N2 gas generator and an air compressor that is capable of inducing intermittent or CH. Results: The hypoxic system we have developed has the following three advantages: (1) It enables persistent exposure to stable levels of intermittent or CH, (2) both the level and duration of hypoxia can be controlled, and (3) it has low initial and running costs. Conclusion: This novel system makes it easy to induce stable hypoxic conditions in the laboratory and has low initial and running costs.