GENERAL MICTAROLISM— HORVATH anb SPURR 



sequent to prior activity. These metabolic gradients are predicated upon enzyme 

 mosaics. Enzyme activity is modified by temperature but the enzymes found in a 

 cell may not have the same thermo-activity characteristics. Therefore, the relative 

 inactivity or stimulation of members of the system alter the substrate and the con- 

 centration of metabolic end products and consequently derange the system. This 

 suggests that the exact temperature of cells and the influence of this temperature 

 level on the components of the cell are the most important factors to be considered 

 in the evaluation of the animal's response to a lowered (basically an altered) body 

 temperature. 



There are considerable differences in the temperature of different parts of the 

 body core and body surface (fig. l).^' Whether similar gradients exist in the hypo- 



JUGULAR 



VEIN 99.0° 



— INNOMINATE 



VEIN 98.7° 



CRANIAL 

 98.9 VENA CAVA 



99.1 AZYGOS VEIN 



99.8° CORONARY SINUS \ 



^ ^^'\ f — PULMONARY ART. 99.4° 



99.4" 



99.6° ^^^^^ ^^'^ 



99.4° DEEP CIRCUMFLEX 

 ILIAC VEIN 



99.4° 

 99.0° 



FEMORAL ART. rr/- 



98.0° MUSCLE - 

 91.2° SKIN 



92.5' 



SUBCU. 



99.4' 

 CAUDAL 98.6° 

 VENA CAVA 98.5° 



98.2° 



EXTERNAL 97.4° 



ILIAC VEIN 96.3° 



FEMORAL VEIN 96.4° 



Fig. 1. — Thermal gradients in blood and various tissues of the dog. 

 Ambient temperature = 22.2° C. 



