Ultrastructural alteration of pulmonary tissue under conditions of high oxygen concentration

Hirohisa Yano; Ayumi Kuroda; Hideshi Okada; Hiroyuki Tomita; Kodai Suzuki; Chihiro Takada; Hirotsugu Fukuda; Yuki Kawasaki; Isamu Muraki; Yugo Wakayama; Soichiro Kano; Yuto Tamaoki; Ayane Nishio; Risa Inagawa; So Sampei; Ryo Kamidani; Yoshinori Kakino; Ryu Yasuda; Yuichiro Kitagawa; Tetsuya Fukuta; Takahito Miyake; Norihide Kanda; Nagisa Miyazaki; Tomoaki Doi; Takahiro Yoshida; Akio Suzuki; Shozo Yoshida; Shinji Ogura

Ultrastructural alteration of pulmonary tissue under conditions of high oxygen concentration

Int J Clin Exp Pathol. 2020 Dec 1;13(12):3004-3012. eCollection 2020.

Authors

Hirohisa Yano¹, Ayumi Kuroda¹, Hideshi Okada¹, Hiroyuki Tomita², Kodai Suzuki¹, Chihiro Takada¹, Hirotsugu Fukuda¹, Yuki Kawasaki¹, Isamu Muraki¹, Yugo Wakayama¹, Soichiro Kano¹, Yuto Tamaoki¹, Ayane Nishio¹, Risa Inagawa¹, So Sampei¹, Ryo Kamidani¹, Yoshinori Kakino¹, Ryu Yasuda¹, Yuichiro Kitagawa¹, Tetsuya Fukuta¹, Takahito Miyake¹, Norihide Kanda¹, Nagisa Miyazaki³, Tomoaki Doi¹, Takahiro Yoshida¹, Akio Suzuki⁴, Shozo Yoshida¹, Shinji Ogura¹

Affiliations

¹ Department of Emergency and Disaster Medicine, Gifu University Graduate School of Medicine Gifu, Japan.
² Department of Tumor Pathology, Gifu University Graduate School of Medicine Gifu, Japan.
³ Department of Internal Medicine, Asahi University School of Dentistry Mizuho, Gifu, Japan.
⁴ Department of Pharmacy, Gifu University Hospital Gifu, Japan.

PMID: 33425101
PMCID: PMC7791376

Abstract

Objective: To determine the structure of pulmonary tissue under conditions of high oxygen concentration.

Methods: Ten-week-old C57BL male mice and control mice were exposed to 100% oxygen and to room air for 72 hours, respectively. To follow the progression of lesions, the mice were sacrificed at 6, 12, 24, 48, and 72 hours after 100% oxygen administration. Lung specimens obtained from these mice underwent morphologic analysis and immunofluorescence studies. We used scanning and transmission electron microscopy to determine the ultrastructure of the pulmonary capillaries, including the endothelial glycocalyx. To visualize the endothelial glycocalyx, we performed lanthanum nitrate staining.

Results: The survival rate of the 100% oxygen administration group was 5% (2/40) and that of the control group was 100%. Perivascular cavity enlargement was detected 12 hours after 100% oxygen administration and expanded over time. Ultrastructural analysis using electron microscopy revealed collapsed alveoli and pulmonary capillary wall and alveolar wall thickening in the 100% oxygen group. The pulmonary capillary endothelial glycocalyx was injured in the 100% oxygen group. The perivascular cavity decreased in mice that were returned to room air after 48 hours of 100% oxygen administration.

Conclusion: High-concentration oxygen causes perivascular cavity enlargement; this is thought to be a special characteristic of high oxygen damage. In addition, high-concentration oxygen may be involved in pulmonary endothelial glycocalyx injury.

Keywords: Hyperoxic acute lung injury; endothelial glycocalyx; microcirculation disorder.