Influence of Calcium and Barium on the Kidney. 183 



In this experiment, although the flow of urine has been consider- 

 ably increased by the injection of "Vs NaCl, the introduction of 

 CaClo markedly suppresses the secretion. The flow of urine remains 

 small for an hour, although a somewhat greater quantity of fluid 

 is forced into the blood than in the previous hour. This suppres- 

 sion of urine is at once counteracted by the injection of sodium 

 citrate. 



The following table (3) which represents only the latter half 

 of an experiment shows roughly the duration of the action of 

 smaller doses of calcium. 



3. Rabbit — cannula in bladder — injections intravenous. 



Salts other than Vg NaCl in- Urine in 

 Time. NaCl injected. jected in cc. cc. 



9.25 



1.40 150 64.5 



1.45 10 6.G 



1.50 10 5.6 



1.55 10 6.2 



2.00 10 7.4 



2.05 10 9.5 



2.05 5 cc Vs CaCls 



2.10 5 2.2 



2.15 10 0.8 



2.20 10 1.2 



2.25 10 1.6 



2.30 10 2.8 



2.35 8 3.0 



2.40 5 4.5 



2.45 o 4.8 



2.50 o 5.1 



2.55 O 6.2 



As shown here and in other experiments, the action of calcium 

 is only temporary. I have found also that magnesium chloride 

 in many cases has cin antidiuretic action similar to that of calcium 

 chloride. The suppression of urine, however, is not so marked 

 as with calcium. 



As shown in the following experiment (4) barium chloride in 

 very small doses has a strong diuretic action. Although it is 

 much more powerful in this respect than sodium citrate, the in- 

 creased flow of urine which it causes may be suppressed by the 

 injection of calcium chloride. 



