KIDNEY 



171 



KIDNEY 



vivo of the surface of the guinea pig'a 

 kidney, and for the marking of single 

 tubules with India ink for their later 

 isolation by maceration, is given by 

 Walker, A. M. and Oliver, J., Am. J. 

 Physiol., 1941, 134, 562-595. The micro 

 collection of fluid from single tubules 

 is as the authors state a direct continu- 

 ation of the researches of A. N. 

 Richards. See Oliver, J., Harvey Lec- 

 tures, 1944^5, 40, 102-155. 



Vital staining of kidney tubules is a 

 valuable method for "seeing" func- 

 tional activity in morphological form. 

 It is usually carried out by techniques 

 not requiring special adaptation. See 

 Vital Staining. The procedure em- 

 ployed by Oliver, J., Bloom, F. and 

 MacDowell, M., J. Exp. Med., 1941, 

 73, 141-160 deserves mention because 

 it gives a clear demonstration that the 

 cells of abnormal proximal convoluted 

 tubules can be marked by their inability 

 to concentrate trypan blue which con- 

 sequently stains the tubule wall 

 diffusely. This is illustrated in colors. 

 Microscopic observations, having a 

 close relation to function, are easily 

 made on the kidneys of lower forms. 

 See the account of contractility of the 

 ciliated necks of renal tubules in Nec- 

 turus by Lucas, A. M. and White, H. 

 L., Anat. Rec, 1933, 57, 7-11. The 

 functional handling of fluorescent dj^es 

 by the amphibian kidney may be ob- 

 served microscopically in vivo by means 

 of ultraviolet light (Ellinger, P., Quart. 

 J. Exp. Physiol., 1940, 30, 255, and 

 Singer, E., Anat. Rec, 1936, 66, 343). 

 The amphibian kidney also lends itself 

 to the application of the "extra-vital" 

 method where the functional activities 

 (secretion of dyes) of the isolated per- 

 fused kidney are correlated with the 

 structural aspect of the process by 

 subsequent histological examination 

 (Oliver, J. and Smith, P., J. Exp. Med., 

 1931, 53, 785; Oliver, J. and Lund, E. A., 

 Ibid, 1933, 57, 435). 



The study of the renal tubules present 

 in tissue cultures is useful in the study 

 of function. Thus Chambers, R. and 

 Cameron, G., Radiology, 1941, 37, 

 186-193 have found that susceptibility 

 to x-rays is increased when a secretory 

 stimulant is added but that in cultures 

 it is distinctly less than in vivo. See 

 references accompanying this paper. 



A method has been devised by Crab- 

 tree, C. E., Endocrinology, 1941, 29, 

 197-203 of measuring by a differential 

 count the number of Bowman's capsules 

 made of cuboidal as contrasted with 

 squamous cells. The count appears to 

 provide an index of age and sex varia- 

 tions in normal mice and of the in- 



fluence of testosterone propionate on 

 castrated mice. The glomeruli may 

 also be counted in aliquot portions of 

 macerated renal cortex and decreases 

 in their number correlated with the 

 abnormal conditions of disease or 

 senility (Aratabi, M., Am. J. Anat., 

 1926, 36, 399). 



Methods for estimating the distribu- 

 tion of enzymes in the tissue components 

 of the rabbit's kidney are given by 

 Weil, L., and Jennings, R. K., J. Biol. 

 Chem., 1941, 139, 421-432. They de- 

 pend on topographic correlation be- 

 tween distribution of cell types in 

 15 ft frozen sections and decomposition 

 of substrates. The techniques are ca- 

 pable of demonstrating catheptic, ami- 

 nopolypeptidase and esterase activities 

 in all of the epithelial components and 

 of showing that the cells of the proximal 

 and distal convoluted tubules are about 

 twice as active enzymatically as those 

 of the ascending and descending loops 

 of Henle and about 4 times as active as 

 the cells of the collecting tubules. 

 Amylase and dipeptidase activities can 

 also be localized and expressed quanti- 

 tatively in relative terms. 



For the application to proximal con- 

 voluted tubules in phlorizin glycuresis 

 of the Kabat and Furth procedure for 

 alkaline phosphatase see Kritzler, R. A. 

 and Gutman, A. B., Am. J. Physiol., 

 1941, 134, 94-101. See Phosphatase. 

 Lipase may also be shown by the pro- 

 cedure of Gomori, G., Arch. Path., 

 1946, 41, 121. 



Techniques capable of revealing very 

 interesting data on the shape of cells of 

 the proximal tubule have been devised 

 and employed by Foote, J. J., and 

 Grafflin, A. L., Am. J. Anat., 1942, 70, 

 1-20. They can probably be employed 

 to advantage in different functional 

 states and to other than renal cells. 



Methods have been elaborated for 

 measurement of the renal filtration sur- 

 face and data have been supplied for 

 the albino rat (Kirkman, H. and 

 Stowell, R. E., Anat. Rec, 1942, 82, 

 373-389). The original paper should 

 be consulted. See also the measure- 

 ments of glomerular number and size 

 in various species by Rytand, D., Am. J. 

 Anat., 1938, 62, 507. A valuable collec- 

 tion of measurements of renal struc- 

 tures will be found in v. Mollendorf- 

 Handbuch d. mikr. Anat., 1930, VII-1, 

 20-34. 



pH determinations can be made as 

 described by Emmel, V. M., Anat. Rec, 

 1940, 78, 361-377 by means of a capillary 

 glass electrode (Voegtlin, C. and 

 Kahler, H., Science, 1932, 75, 362) and 

 a vacuum tube potentiometer (Hill, 



