Effects of Space Cabin Environments on Resistance of Mice to Infection with Klebsiella Pneumoniae

摘要

This study shows the effect of exposure of mice to an altitude of 35,000 feet and to an atmosphere consisting of approximately 85% oxygen, 10% carbon dioxide, and 5% nitrogen for 3, 7, 14, and 30 days on susceptibility to respiratory infection caused by aerosols of Klebsiella pneumoniae. Mice exposed to 35,000 feet for 14 days prior to challenge and then returned to 35,000 feet exhibited an increase in mortality from 37% to 76%. 'Mice exposed to 35,000 feet for 14 days prior to challenge and then kept at ambient altitude exhibited an increase in mortality from 37% to 53%.'There was an increased neutrophilic percentage accompanied with a lower white cell count in the blood of mice exposed to 35,000 feet for 14 days. Mice lost weight initially when placed at 35,000 feet. They started gaining weight after about 2 weeks, and the rate of weight gain was approximately that of mice kept at ambient altitude. Mice kept at 35,000 feet consumed more food than mice kept at ambient altitude. (Author)