164 LOCAL TLSSUE REACIIVLIY 



petechial k'sioiis. wliic Ii (onsistcd nii( rose ()j)i{ally ol (apillaiy dila- 

 tation and extraxasaiion oi erythrocytes. Enhanced liability ol the 

 capillaries in sites distant from the local reaction coidd be denicjn- 

 strated lor a pci iod ol loin- to lort)-eii>ht hours lollowin'^ the j)r()- 

 v()cati\e injection ol the actixe j)iin(iples and depended on the 

 sexerity ol the local lesion. 



Gratia and Linz (i9'^2c) noticed that alter the intravenous ])ro- 

 \()cati\e injection of the active principles, pnlling of hair, or slight 

 traimia in sites distant from the site of the typical reaction 

 produced petechial hemorrhages xvhich sometimes became 

 conlluent. The obser\ations demonstrating enhanced capillary 

 fragility at sites distant from the local reactions deserve further 

 investigations. Koplik (1937) reported that following the intrader- 

 mal injection the preparatory factors may spread to adjacent lymph 

 nodes by way of the lymphatics. It is possible, therefore, that the 

 factors diluted in the lymph prepare distant sites for a reaction of 

 lesser severity. The mild reaction thus obtained may then, in turn, 

 be enhanced by additional mechanical stimidation. The other 

 possibility is that there form at the site of local reaction some 

 secondary diffusible toxic substances xvhich by themselves modify 

 the capillary response to stimidation in sites distant from the local 

 reaction. 



I also attempted to determine the rate of diffusion of saline in- 

 jected prior to the provocative injection, into sites prepared by 

 bacterial filtrates. Blebs produced by an injection of 0.5 c.c. of 

 saline into the prepared sites and into normal sites persisted for 

 an equal length of time, i.e., approximately thirty minutes. 



Bmnet (1931) injected intra\enously 1 to 2 c.c. of 1 per cent 

 solution of trypan blue at different periods after the provocative 

 injection Avas gi\en. There xvas no e\idence that any increased per- 

 meability of capillaries in the prepared areas preceded the appear- 

 ance of purpina. The slightly indurated prepared sites appeared 

 dehnitely less blue than the surrounding skin until the commenc- 

 ing pmpura ^vas clearly visible. Later there A\as a uniform staining 

 of the skin. The obser\ation xvas confnmed by P. Borxlet. 



MORPHOLOGICAL STUDIES ON THE PHENOMENON 



In recent years there apj)eared a group of extensixe histological 

 studies on the reaction of the phenomenon of local tissue reactiv- 



ity. 



Karsner and jVIoritz (1934) state that the preparatcny injection 



