CONTROL OF BOD1 TEMPEBATUR1 \m« PEVEB >-■> 



elimination of chlorides is going on. Chlorides and water would th< 

 fore seem to behave in a similar fashion during fever. 



The Heat-regulating Center 



In all discussions on the regulation of body temperature and the 

 causes of fever, it is assumed that a I igulating or thermogenic 



center exists somewhere in the brain. It is believed to b< 

 about the optic thalami or corpora striata, for it lias been found in 

 rabbits that destruction of the brain anterior to this region does 

 cause any change in body temperature, whereas destruction behind it 

 is followed by an entire upset in the heat-regulating mechanism. Fur- 

 thermore, artificial puncture of this part of the brain causes marked 

 elevation in body temperature in rabbits (heat puncture). Most in- 

 teresting experiments have been recorded by Barbour, 58 who - eded 

 in applying boat or cold locally in the region of the centers. By the 

 application of cold, increased muscular metabolism, on t lie one hand, 

 and diminished heat loss, on the other, were excited; and conversely, 

 when warmth was applied, an increased heat loss and a diminished I 

 production were observed. Irritation of this region of the brain in man. 

 as after cerebral hemorrhage, is also accompanied by remarkable dis- 

 turbances in heat regulation. Tt is believed by many that the essential 

 cause of infectious fever is an action on these centers by toxic substai 

 which develop in the blood. 



The centers may also be acted on by various drugs, some of which 

 excite them to increase the body temperature, others, to lower the tem- 

 perature when this has already been elevated. When solutions of sodium 

 chloride are injected intravenously or subcutaneously or even sometu 

 particularly in children, when administered by month, more or 



may result. This must be a s| itie action of the Na ion, for, if 



of pun solutions o \ CI. solutions containing calcium and potassium 

 salts as well as tho sodium are injected, no fever is induced. This 



fact, taken along with the close similarity between puncture dial ■ 

 and heal puncture, lends support to the view thai in its initial 

 experimental fever of this type is the result of an excessive breakdown 

 of glycogen in the liver. It must not be imagined, ho . that | 



cut fever can be attributed to such a cause, sin.- er remaii 



the glycogen has all been removed. Other chemical substanci duc- 



ing fever are caffeine, certain Other purines, and particularly tetra-hy 



naphthylamin. 



Belonging to this group of fevers musl he im- 



portant ones produced by the intravenous injection D - 



protein, as 1 rom th< 



