88 (152) Society for Experimental Biology and Medicine. 



III. " The effects of intravenous injections of radium bromid" : 

 Russell Burton-Opitz and G. M. Meyer (Physiological Labora- 

 tory, Columbia University). 



These experiments, dealing principally with the effects of 

 radium bromid upon the circulation and respiration, were per- 

 formed upon dogs weighing from 4 to 5 kilos. Light ether-nar- 

 cosis was employed. The solutions injected contained 1.8 mg. of 

 radium bromid per c.c. of distilled water. Preparations of radium 

 bromid of 240, 1,000, and 10,000 activity were used. The facial 

 vein was selected for the injections. 



Injection was always followed, after a latent period of about 

 five seconds, by a gradual and well marked increase in blood-pres- 

 sure, this rise evidently being caused by general vaso-constriction. 

 Soon, however, a marked decrease in the frequency of the heart, 

 accompanied by a pronounced irregularity, causes a fall in pressure. 

 Contractions in which the diastolic phase is extremely conspicuous 

 interchange with a series of forcible preeminently systolic beats. 

 It need hardly be mentioned that under these conditions the varia- 

 tions in blood-pressure are extreme. These effects of radium occur 

 also after both vagi have been divided. 



The circulatory effects are accompanied by a gradual decrease 

 in the frequency of respiration, terminating finally in complete 

 respiratory paralysis. This effect precedes the total inhibition of 

 the heart. 



All ordinary preparations of radium salts contain barium. In 

 order to check the effects of such impurities, the authors carried 

 out a number of comparative experiments with pure barium bromid. 

 It was found that the effects of radium bromid preparations of low 

 activity (240 and 1,000) differ only quantitatively from those of 

 barium bromid. Certain amounts of such radium preparations 

 produce effects that can be obtained only by correspondingly larger 

 amounts of barium bromid. The influence of barium in causing 

 pronounced irregularity of the heart is not evidenced by the 

 preparations of radium bromid of 10,000 activity ; only a marked 

 inhibition results, which is accompanied by a decided rise in 

 blood-pressure. 



IV. " The radioactivity of the different organs after intravenous 

 injections of radium bromid" : Gustave M. Meyer (Laboratories 

 of Physiological Chemistry and Physics, Columbia University). 



