EFFECTS ON PERMEABILITY AND ACTIVE TRANSPORT 193 



the kidney were undoubtedly different, although it is difficult to compare 

 these because Herms and Malvin injected the iodoacetate at 0.06-0.124 

 used instead of iodoacetamide, however, and the concentrations reaching 



mg/kg/min. They observed no consistent changes in urine volume and little 

 effect on Na+ or K+ transport, except for a marked reduction in K+ secre- 

 tion in the collecting ducts. Angielski et al. (1960 a) injected iodoacetate 

 into rats at a dose of 0.11 millimole/kg and found the urine flow to be 

 30-40% reduced for several days, in contrast to the effects produced by 

 the mercurials (see Table 2-6). The marked aminoaciduria, so characteristic 

 of the actions of the mercurials and maleate, is also not seen with iodo- 

 acetate. 



Ion Transport through Frog Skin 



A net transport of NaCl and water across frog skin can be demonstrated, 

 and simultaneously there is some active accumulation of K+ intracellularly. 

 The inhibitions of net transport and accumulation do not necessarily run 

 parallel. The effects of iodoacetate are shown in the accompanying tabula- 

 tion and in Fig. 1-13 (Huf ct al., 1957). Iodoacetate belongs to that class of 



% Change due to iodoacetate at: 



inhibitors which depresses net transport somewhat more readily than Na+ 

 extrusion and does not significantly inhibit respiration. Contrary to the re- 

 sults in other tissues, it also causes a somewhat greater Na+ uptake than 



