Scientific Proceedings. ( 22 5) 55 



other is a lower reflex, consisting of a chain of local reflexes which 

 are very resistant to anesthesia. 



The complexity of their mutual relations furnishes suggestive 

 problems for future investigations. 



30 (122). " The enzymes of inflammatory exudates. A study 

 of the enzymes concerned in inflammation and their rela- 

 tion to various types of phagocytic cells " : EUGENE L. 

 OPIE. 



The leucocytes of an inflammatory exudate produced by inject- 

 ing aleuronat into the pleural cavities of dogs digest protein both in 

 an alkaline and in an acid medium (uncoagulable protein nitrogen 

 being estimated by the Kjeldahl method). The following evi- 

 dence shows that two enzymes are present : 



(a) Cells, dried after treatment with absolute alcohol and ether 

 and then reduced to a powder, digest actively in an alkaline 

 medium (0.2 per cent, sodium carbonate), but have almost com- 

 pletely lost the power of digesting in an acid medium (0.2 per cent, 

 acetic acid). 



(b) By subjecting washed cells of a sterile inflammatory exu- 

 date to varying degrees of heat, their power to digest in an alka- 

 line and in an acid medium is lost at a temperature above 70°" 

 C. At temperatures between 5 5 0 and 65 0 C. the power to digest in 

 an alkaline medium is unimpaired but in an acid medium it is 

 much diminished. 



(c) With cells of exudate removed from the pleural cavity 

 twenty-four hours after the injection of aleuronat, digestion is very 

 active in an alkaline medium, but less active in an acid medium. 

 At the end of from three to five days, power of digesting in an 

 alkaline medium is diminished or unchanged, but the acid digest- 

 ing power is increased. 



At the end of twenty-four hours after injection of aleuronat 

 polynuclear leucocytes with fine granulation are predominant and 

 from 85 to 90 per cent of the cells are present. The cells, accord- 

 ing to observations previously reported, contain a ferment with acts 

 in an alkaline medium. At a later stage of inflammation when 

 large mononuclear phagocytic cells are predominant, the power of 

 digesting in an acid medium is increased and bears a relation 

 to the proportion of mononuclear phagocytes. If washed red 



