1912'] A Study of the Action of Diuretics 5 



mal. During the period of preliminary observation the urine 

 was collected daily, measured and studied qualitatively and 

 microscopically. The existence of a naturally acquired nephritis 

 was excluded. Two of the animals showed the presence of 

 albumen and erythrocytes in the urine but no casts. 



At the end of three or four days, after the preliminary data 

 had been obtained, the animals were given from 5 to 10 mgs. of 

 uranium nitrate subcutaneously. The frequency with which 

 the injections were repeated was determined by the severity of 

 the nephritis produced by a given injection and by the stage of 

 the nephritis that was desired in which to study the action 

 of the different diuretic substances. Such a method of regulat- 

 ing the quantity of nephrotoxic substance is more accurate, so 

 far as the reaction on the part of the kidney is concerned, than 

 can be obtained by using a constant quantity of the kidney 

 poison per kilogram of body weight, since different animals 

 vary very greatly in their response to the same quantity of the 

 poison. 



Usually within twelve or twenty-four hours after the initial 

 injection of uranium the animals had developed a well-marked 

 nephritis. 



Occasionally on the first day of the nephritis, and almost 

 invariably by the second day, the animals developed a pro- 

 nounced glycosuria. The quantitative output of albumen was 

 not determined. Quantitative sugar determinations were made 

 with both Fehling's and Purdy's quantitative reagents. These 

 determinations showed that the output of sugar in a twenty-four 

 hour specimen of urine varied from 0.25 to 3.22 per cent. 



After the production of the nephritis the animals were 

 anesthetized with either morphine-ether or Grehant's anes- 

 thetic.^ 



The following operative technique was constantly employed. 



A tracheal canula was tied in place and connected with the 

 ether bottle to be used in case additional anesthetic was neces- 

 sary during the experiment. 



' Orehant's Anesthetic. The animal is given Vi ec. per kilogram of a 4 per 

 cent solution of morphine. This is followed in half an hour by 10 ce. per kilo- 

 gram of the following mixture : Chloroform, 50 cc. ; alcohol and water, each 

 500 cc. 



