NERVOUS CONTROL OF TEMPERATURE. 



859 



increased, and if the augmentation of the latter was not excessive, the 

 temperature of the body rose. On the other hand, Riegel 1 found that 

 the production of heat was diminished, and he explains the rise of 

 temperature in Naunyn and Quincke's cases as due to absence of the 

 rapid breathing whereby normal dogs regulate their temperature. 

 Further, Schroff 2 found a rise in the temperature of dogs when they 

 were kept in a warm chamber after opening of the spinal canal, without 

 damage to the spinal cord. 



Eosenthal 3 repeated Naunyn. and Quincke's experiments, but never 

 found any rise of temperature, unless the animals were kept in a 

 chamber warmed to 32. If the section was made lower down in the 

 cord, more muscles remained under the control of the animal, and by 

 the contraction of these muscles more heat was produced, and the 

 temperature raised when the external air was warm. Rosenthal further 

 points out that it is probable that septic fever was the cause of the rise 

 of temperature in some of Naunyn and Quincke's dogs. 



Pfliiger's 4 experiments upon the respiratory exchange of rabbits, after 

 section of the spinal cord in the lower cervical region, show that such 

 an animal is comparable to a cold-blooded animal; a rise in external 

 temperature increases, a fall diminishes, the metabolism and the 

 temperature of the animal. The same result is even more markedly 

 shown in the case of a smaller animal. Thus the following figures 

 show the effect of sudden changes in the external temperature upon the 

 output of carbon dioxide of a mouse before and after section of the spinal 

 cord in the lower cervical region : 5 



We may conclude, therefore, that in animals the general effect of 

 section of the spinal cord in the lower cervical region is a fall in the 

 temperature of the body, due to a reduction in the metabolism of the 

 paralysed muscles, and to excessive loss of heat consequent upon the 

 vasomotor paralysis. The exceptional cases appear to be due to a high 

 external temperature, and to interference with the rate of respiration, 

 which in dogs plays an important part in the cooling of the body. 



1 Arch.f. d. ges. Physiol., Bonn, 1872, Bil. v. S. 629. 



3 Siteungsb. d. Jc. Akad. d. Wissensch. Math.-natunv. 01., Wien, Bd. Ixxiii. Abth. 3, 

 S. 141. 



3 "Zur Keimtniss d. Warmereguliermig bei den warmbliitigen Thieren," S. 35 ; Hermann's 

 " Handbucb," Bd. iv. Th. 2, S. 437. 



4 Arch.f. d. ges. Physiol., Bonn, 1878, Bd. xviii. S. 321. 



5 Pembrey, " Proc. Physiol. Soc.," Journ. Physiol., Cambridge and London, 1894- 

 1895, vol. xvii. 



