Acute pulmonary and splenic response in an in vivo model of whole-body low-dose X-radiation exposure

Abstract

Purpose: Diagnostic radiation is an important part of patient care in the Intensive Care Unit; however, there is little data on the acute effects of exposure to these doses. We investigated pulmonary and splenic response 30 minutes, 4 hours or 24 hours after exposure to 2 mGy, 20 mGy, 200 mGy or 4 Gy whole-body X-radiation in a Sprague Dawley rat model.

Materials and methods: Lung injury was assessed via respiratory mechanics, pulmonary edema, cellular, and proteinaceous fluid infiltrate and protein expression of oxidative stress markers. The radiation effect on the spleen was determined via proliferation, apoptosis and protein expression of oxidative stress markers.

Results: All measurements of the lung did not differ from sham animals except for an increase in catalase after high dose exposure. Stimulated splenocyte proliferation increased after sham and low dose exposure, did not change after 200 mGy exposure and was significantly lower after 4 Gy exposure. The number of apoptotic cells increased 4 hours after 4 Gy exposure. There were fewer apoptotic cells after low dose exposure compared to sham. Both catalase and MnSOD were increased after 4 Gy exposure.

Conclusion: There was no measured effect on pulmonary function while there was an impact to the spleen after low and high dose exposure.

Keywords:

• Low dose
• X-radiation
• respiratory mechanics
• spleen

Acknowledgments

We would like to thank Dr. Alison Elder, Dr. Shailesh Bihari and Elena Cavallaro from Flinders University for their aid in technique training and analysis of the data.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Sciences and Engineering Research Council [RGPIN/6700-2015] and Bruce Power [BP-5-11].

Notes on contributors

Stephanie Puukila

Stephanie Puukila is a postdoctoral Researcher at Flinders University and Laurentian University in radiation biology.

Stacy Muise

Stacy Muise is a Master's degree graduate from McMaster University in Medical Physics.

James McEvoy

James McEvoy is a PhD candidate and Flinders University and McMaster University in radiation biology with focus on radiation exposure during pregnancy and development of the respiratory statement.

Tara Bouchier

Tara Bouchier works as a Research Assistant in the Lung Injury Research Laboratory at Flinders University.

Antony M. Hooker

Antony M. Hooker is a Research Associate Professor in the College of Medicine and Public Health, Flinders University and School of Chemical Engineering at The University of Adelaide. He is studying the biological mechanisms of low dose alpha and X-radiation.

Douglas R. Boreham

Douglas R. Boreham is a Professor and Division Head of Medical Sciences at the Northern Ontario School of Medicine and Professor in the Department of Medical Physics and Applied Radiation Sciences at McMaster University. He is also Principal Scientist and Manager of the Integration Department at Bruce Power.

Neelam Khaper

Neelam Khaper is an Associate Professor of Physiology at Northern Ontario School of Medicine at Lakehead University. She studies pathophysiology and novel therapeutic approaches of heart failure using various experimental model with specific focus on the role of oxidants and antioxidants in cardiac remodeling.

Dani-Louise Dixon

Dani-Louise Dixon is Associate Professor in the College of Medicine and Public Health, Flinders University and Division of Medical Sciences, Northern Ontario School of Medicine. She studies acute and chronic lung injury with particular emphasis on leukocyte activation, inflammatory resolution and repair, and the implications on pulmonary function.