MECHANISM OF RENAL SECRETION 81 



phthalein are recorded by Potter and Bell (30) in rabbits and 

 Pearce and Ringer (94) in dogs. 



Group C (chromate nephritis). Chromates, as do uranium 

 and tartrates, cause damage to the convoluted tubules. The 

 effects produced are practically the same as by uranium nitrate. 

 In our experiments (K90 and K92) a granular degeneration with 

 some vacuolization was virtually confined to the convoluted 

 tubules, although there was some swelling of the cortical rays. 

 Suzuki (26) believes that this poison affects only the proximal 

 convoluted tubules. 



The functional analysis of these experiments is greatly handi- 

 capped by the introduction of a complicating watery diarrhea 

 from the subcutaneous administration of sodium chromate. 

 The animal of experiment K90 died before iron was given. 

 In K92 only one sample of urine positive for iron was obtained 

 and that contained only a very slight amount. Apparently, 

 therefore, the block to iron secretion with chromates is similar 

 to that with uranium and tartrates, but this series cannot be 

 used as giving conclusive results. Green (91) demonstrated a 

 fall in urinary nitrogen in chromate nephritis corresponding to 

 that of uranium poisoning (89, 90). 



Group D (sublimate nephritis). Mercuric bichloride or cor- 

 rosive sublimate is a well-known nephritic agent. It also affects 

 the convoluted tubules (Wandervelde (95), Pearce (31)). 

 Suzuki (29) states that the lower part of the proximal convoluted 

 tubules is affected and Pearce (31) adds that there is also some 

 damage to the ascending loop of Henle. There is rapid necrosis 

 and cast formation with little previous change noticeable. 

 Clinically, sublimate poisoning is characterized by a severe 

 degenerative parenchymatous nephritis which locks the door to 

 further elimination of the poison and therefore diuretic stimula- 

 tion is of little avail in ridding the system of the bichloride. 



In the first sublimate experiment the rabbit died three and 

 three-quarters hours after the injection of iron, having had a 

 convulsion similar to those arising spontaneously from the toxic, 

 unsaturated form of ferric ammonium citrate. Usually these 

 convulsions did not appear for from nine to thirty hours after 



