EFFECT OF HYPOBARIC ENVIRONMENTS ON THE SUSCEPTIBILITY OF MICE TO BACTERIAL TOXINS
Progress rept. Jan-May 1969
SCHOOL OF AEROSPACE MEDICINE BROOKS AFB TX
Pagination or Media Count:
Two toxin-producing bacteria, Staphylococcus spp. and Salmonella enteritidis, affect man and other animals. Staphylococci produce enterotoxin of the B type SEB that is responsible for food poisoning. S. enteritidis produces a lipopolysaccharide LPS that is both pyrogenic and toxic for humans. SEB and LPS together act as synergists in mice. Neither toxin, separately, is markedly lethal. Injected in sequence, they cause substantial lethality. Twenty-one experiments were conducted at 27,000 ft. simulated altitude with varying gaseous environments and temporal sequences of SEB- and LPS injections in mice. These studies established that hypobaric environments decreased the susceptibility of mice to the lethal effects of the SEB-LPS combination when the animals remained at altitude. This was true whether the mice were acclimatized or not and regardless of the gaseous composition. Greatest resistance or least susceptibility to toxins was demons was demonstrated at 27,000 ft. simulated altitude with 50 O2-50 N2.
- Stress Physiology