﻿PHARMACOLOGICAL ACTIOX OF URANIUM 



13 



drawn and a little of the uraninm solution was again drawn into 

 the syringe. In this manner but veiy little opportunity was af- 

 forded for air to enter the syringe, which was filled Avith dark 

 venous blood diluted with uranium solution. It was found that, 

 so long as no air entered t'iie syringe, the blood remained dark 

 and very venous in appearance. But so soon as the contents of 

 the syringe Avere emptied out into an open test tube and well 

 aerated, the bright red arterial color at once appeared. This ex- 

 periment is significant, inasmuch as it would appear to indicate 

 that oxygen can readily pass through the walls of the red cor- 

 puscles and form a combination with the h?emogiobin within. Since 

 it is not possible to detect any difference spectroscopically between 

 normal blood and blood to Avhich uranium has been added, it there- 

 fore becomes difficult to see how uranium could retard the reduc- 

 tion of oxyhsemogiobin so far as the blood itself is concerned. For 

 if oxygen can readily pass into the corpuscles, and no special com- 

 bination between the uranium and the haemoglobin is formed, then 

 it would seem thai the oxygen might also readily pass out of the 

 corpuscles again. 



The bright red color which blood treated with uranium as- 

 sumes in the air is not appreciably affected by the addition of 

 disodium hydrogen phosphate. It seems probable that the reten- 

 tion of this color is, partly at least, due to changes in the proteids 

 of the red cells. For the color of laked blood is not materiallj^ 

 influenced by the addition of uranium. 



If a sample of fresh blood be treated with uranium and diluted 

 to a one or two per cent solution, and left standing in a stoppered 

 bottle, it will become dark and show decomposition within one or 

 two days. If a similar sample of blood be treated with a solution 

 of potassium cyanide of corresponding strength and then be sim- 

 ilarly diluted and left standing, it will retain its bright red color 

 for several weeks. 



It seems that no chemical combination whatever is formed be- 

 tween uranium and the haemoglobin of tlie blood. In order to test 

 tMs I made a long series of observations both with the spectroscope 

 and with the diffraction grating. In the latter case photographic 

 records were made^^. I was unable to detect by either method any 

 difference between normal blood diluted to one per cent or one-half 

 per cent and blood which had been first treated with uranium and 

 then diluted to one or one-half per cent. A comparison was also 



111 am greatly indebted to Prof. R. R. Ramsey of the Department of Physics 

 of Indiana University for much valuable assistance in making the photographic 

 observations. 



