Influence of Calcium and Barium on the Kidney. 187 



able however that this action of calcium may coexist with its char- 

 asteristic action in diminishing the secretory activity of the kidney. 

 In both the intestine and the urinary apparatus (kidney, and 

 urinary passages) barium stimulates the glandular and the mus- 

 cular tissues to activity. Calcium on the other hand uniformly 

 suppresses these activities. 



It must be pointed out however that the suppression of the 

 flow of urine which follows a relatively large dose of barium 

 chloride cannot always be relieved by calcium. As was found to 

 be true In the intestine, the action of barium Is seldom completely 

 counteracted by calcium. In many cases the barium stops the 

 flow of urine entirely so that it is not possible to start it again. 

 This is shown In the following experiment (6) where relatively 

 large quantities of calcium chloride are incapable of reestablishing 

 the flow of urine. This naturally suggests the idea that the large 

 doses of barium may stop the secretion of urine by injuring the 

 cells of the kidney, or perhaps Indirectly by a constricting influ- 

 ence on the blood vessels. These possibilities must be taken into 

 consideration; but the fact that calcium sometimes causes the 

 urine to flow again after it has been Inhibited by barium speaks 

 strongly In favor of the theory advanced above, that the inhibiting 

 action of barium on the flow of urine Is an action on the mus- 

 cular tissue of the urinary passages. 



6. Rabbit — cannula In bladder; Injections Intravenous. 



Salts other than '"/s NaCl In- Urine in 



Time. NaCl Injected. jected In cc. cc. 



9.50 



10.20 23 



10.30 20 



10.40 25 



10.50 28 



11.00 20 



II. 10 16 



11.20 10 



11.30 10 , 



11.40 12 



11.50 15 



1 1.5 I ^ ccVs BaCl2 



11.55 i-o 



