SUMMARY 



piratory tract of dogs or rats (Nungester and Jourdonais , 19 36) . Also, 

 pneumococci and mucin placed in the nose of rats will produce ex- 

 perimental pneumonia under certain conditions which alter the nor- 

 mal physiological defense mechanisms (Nungester and Klepser, 

 1938), But do such findings have any relation to cold and respiratory 

 tract infections? 



Mudd et al. (1921) have shown that an uneven cooling of skin sur- 

 faces causes vascular changes in the nose. It is common for nasal 

 secretions to flow out of the anterior nares when one comes into 

 contact with cold air. Either the ciliary mechanisms fail or there is 

 a marked increase in secretions. It seems to me that the latter is 

 more correct, for it is based on a sudden change in blood supply to 

 the mucus secreting glands. This hypothesis is based on the early 

 findings of Mudd and his colleagues, A marked increase in respira- 

 tory tract secretions based on physiological stimulation (cold air) 

 or infections will overburden the cilia and cause the mucus secre- 

 tions to accumulate in the upper respiratory tract. Such an over sup- 

 ply may drain out the anterior nares, be swallowed, or might pos- 

 sibly be aspirated. Is it possible, then, that marked cooling of the 

 body may increase the chances for aspiration of infected mucus 

 secretions from the upper respiratory tract? 



We have some evidence from our laboratory (Nungester and 

 Klepser, 1938) which showed that the reflex control of the glottis is 

 decreased by body chilling. Mechanical stimulation of the glottis 

 area with a smallwireinlightly anesthetized rats resulted in closing 

 of the glottis in all but 18 per cent of 754 stimulations. With rats 

 chilled for ten minutes in ice water, the glottis did not close in 46 

 per cent of 552 stimulations. In 21 other rats, none of them aspir- 

 ated India ink colored mucin placed in the nose, while 55 per cent of 

 20 rats previously chilled aspirated the material into the lungs. 

 Pneumococcus pneumonia developed in 13 per cent of 46 normal rats 

 inoculated internasally with mucin and pneumococcus. In another 

 group of 24 rats, chilled in ice water and similarly injected, 42 per 

 cent developed pneumonia. These results may or may not be related 

 to severe chilling and pneumonia in man. 



Dr. Tunevall has told us that absorption of tetanus toxin is delayed 

 in the hypothermic animal. This directs our attention to the physi- 



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