EATE OF PENETRATION OF PHOSPHATIDES THROIGH THE CAPILLARY WALL 267 



A2 = 6.5 mgm %; Bg = 7.5 mgm "0; ^o = 4.0 mgm %; D, = 4.8 mgin %)(i). 

 From these variations in the phosj)hatide contents of the plasma we followed that 

 from the data obtained in the first experiment, we cannot calculate the loss of 

 labelled phosphatides by the plasma iu the course of the first 7 min., while we 

 can state the loss sustained in the interval between 7 and 67 min after the start 

 of the experiment. It is this vahu^ which is recorded in Table 4. 



T.\BL.E 4. — Change in the Specific Activity 

 OF the Plasma Phosphatide of Chicks B^, Cj, Dj, Ej, 



AFTER THE INJECTION OF PlASM.\ OF ChICK A^ 



Containing Labelled Phosphatides 



*»> These chicks have shown pronounced exudates due to E-avitaminosis and were kiiully \mt at our 

 disposal by Dr. H. Dam. The injection was kindly carried out by Mrs. Svendsen. The above I'isures do not 

 permit us to draw any conclusion as to a difference in the permeability of, for example, the muscle capil- 

 laries of normal chicks and chicks suffering from E-avitaminosis. To arrive at such a conclusion it wotdd 

 be necessary to compare the labelled phosphatide content of the muscle tissue of normal clucks and of 

 chicks sufferintr from E-avitaminosis at the end of the experiment. 



EFFECT OF HISTAMIN 



We also carried out experiments in which histamin was injected simul- 

 taneously with the plasma containing labelled phosphatides. The results 

 of" these experiments are seen in Table 5. 



The administration of histamin did not much affect the appearance 

 of chicks C3 and D3, while chicks E3 and F3 could not stand on their 

 feet for the first 5—10 min. which elapsed after the injection of histamin. 

 From the last mentioned two chicks, only small blood samples, about 

 0.4 cc, could be secured, while we collected several cc. from chicks 

 which got no or only minor doses of histamin administered. The total 

 plasma volume of the chick was calculated as described on p. 6. The 

 average figure obtained for the labelled phosphatide content of one cc. 

 plasma of chicks C3, D3, E3, and F3, to which histamin was administered, 

 20 min. after the start of the experiment is aboul 7. It is the same 

 figure which was obtaines for the labelled phosphatide content of the 

 plasma of chicks B3 and Bg, Cg, Dg (see Table 3) in one cc. No striking effect 



(1) Comp. also the great variations in the phosphatide content of the blood 

 of chicks found by F. \V. Lokexz, J. L. Ch.a.ikoff and C. Entenmax, J . Biol. 

 Chcm. 123, 577 (1938). 



