288 A CHEMICO-PHYSIOLOGICAL STUDY OF 



The experiments with protogelatose and deuterogelatose in 

 agreement with the observations of Arthus and Huber, fail to 

 show any such marked influence as is obtained with the corre- 

 sponding albumoses. True gelatin-peptone, on the other hand, 

 approaches hemipeptone and antipeptone in the intensity of its 

 action. The great difference which the albuminoid products 

 show, quantitatively at least, in contrast with the derivatives 

 of the native proteids serves to emphasize the other striking 

 differences between gelatin and true proteids as regards physio- 

 logical equivalence.* 



Lastly, attention is directed to the slight initial rise in pres- 

 sure immediately succeeding the injection of the various sub- 

 stances into the circulation as shown in the tracings. This 

 rise, which is undoubtedly due to the rapid entrance of the 

 fluid into the vascular system,! gives evidence of the rapidity 

 with which the injections were carried out. This fact is not 

 without significance, since the variation in effects of intraven- 

 ous injections of proteoses has been demonstrated (cf. Thomp- 

 son) to be dependent in part on the rapidity of the injections. 

 It seems reasonable, therefore, to assume that the intensity of 

 vasomotor effects is not so much a function directly of the 

 absolute quantity injected as of the quantity in the circula- 

 tion per unit of time, or, in other words, of the concentration 

 of the substance in the blood. 



The accompanying blood-pressure tracings have been 

 selected from typical experiments. They were recorded with 

 a mercurial manometer, as already described. The tune is 

 recorded in seconds, and the line of zero pressure is likewise 

 recorded. The curves all read from right to left, and only 

 such portions have been reproduced here as furnish evidence 

 of the observations discussed in the preceding pages. 



tenden, Digestive Proteolysis, 1894, p. 42. Also recent papers from Hof- 

 meister's laboratory. Zeitschr. f. physiol. Chem., 1897-98. 



* Cf . L Munk, Archir f. d. ges. Physiol., 1894, Iviii, p. 309. Also Mendel 

 and Jackson, Amer. Jour. Physiol., 1898, vol. ii, p. 21. 



t Cf. Thompson, Journal of Physiology, 1896, xx, p. 455. 



