POTASSIUM 



201 



phostate 



cobalti -nitrite solution of Biilman 

 (Treadwell, F. P., Analytical Chemis- 

 try, vol. 1, 4th English Ed. translated 

 by W. T. Hall, New York, John Wiley 

 & Sons, Inc., 1916, p. SI). Decant 

 fluid, mount in glycerin in same way and 

 examine. Crystals of sodium potassium 

 cobalti -nitrite are just visible with oil 

 immersion lens. They are short yellow 

 rods with rounded ends in a diffuse pale 

 yellow background soluble at room tem- 

 perature. 



4. Carer-Comes, O., Zeit. f. wis. 

 Mikr., 1938, 55, 1-6 has advised histo- 

 chemical demonstration of potassium 

 by Siena orange (K. Hollborn), which is 

 sodium paradipicrylamine. Deparaf- 

 finize sections of neutral formalin fixed 

 tissue. Place in Siena orange solution, 

 as received ready for use from Kollborn, 

 2 min. Then 10% HCl 3 min. Wash 

 twice in aq. dest. 10 min. Blot with 

 filter paper and dry at 37°C. Mount in 

 thickened cedar oil. Tissues contain- 

 ing potassium, orange; others, pale yel- 

 low or unstained. 



5. Radioactive potassium can be 

 easily measured in tissues and cells. 

 There is 40% penetration of red blood 

 cells in vivo (Mullins, L. J., Noonan, 

 W. O. and T. R. and Halge, L., Am. J. 

 Physiol., (1941, 135, 93-101). See 

 Radiopotassium. 



Preputial Gland of rats. Useful histochemi- 

 cal methods of investigation and 

 changes following thyroidectomy (Mon- 

 tagna, W., Anat. Rec, 1948, 94, 38). 



Pressure. Increase in pressure beyond a 

 certain limit, somewhat characteristic 

 for particular cells (300-1000 atmos- 

 pheres), brings about a liquefaction of 

 the plasmagel which can be directly 

 observed microscopically or determined 

 by certain measurements like action 

 potential for nerve fibers. Danielli 

 (Bourne, p. 38) has expressed the 

 opinion that the factor causing in- 

 hibition of movement may, in all cases, 

 be increased hydration of protein 

 molecules and that the method of in- 

 creased pressure may be of great value 

 to large scale and micro-biologists. 



Price-Carr Reaction, see Carr-Price Reac- 

 tion. 



Primula R Water Soluble, see Hofmann's 

 Violet. 



Primulin (CI, 812) — primuline yellow — An 

 acid thiazole dye used in fluorescence 

 microscopy (Pick, J., Zeit. Wis. Mikr., 

 1935, 51, 338-351). 



Praseodymium, see Atomic Weights. 



Primuline Yellow, see Primulin. 



Prolactan. Methods for assay (Bates, R. 

 W., Cold Spring Harbor Symposium on 

 Quantitative Biol., 1937, 5, 191-197). 



Promyelocytes, see Leucocytes, develop- 

 mental series. 



Prontosil as a vital dye (Carter, W., Science, 

 1939, 90, 394). 



Propylcarbinol, see n-Butyl Alcohol. 



Prostate. This organ cannot be examined 

 microscopically in vivo and supravital 

 staining has not proved very fruitful. 

 The cutting and staining of sections is 

 the conventional method. It is impor- 

 tant that the blocks of tissue fixed be 

 oriented with great care, and that 

 microscopic and gross observations be 

 correlated. For normal size and weight 

 see Moore, R. A., Am. J. Path., 1936, 

 12, 599-624 and for age changes a chap- 

 ter by the same author in Cowdry's 

 Problems of Ageing, Baltimore: Wil- 

 liams & Wilkins, 1942, 936 pp. Since 

 the structure of the prostate exhibits 

 so many local differences there is a 

 danger of erroneous conclusions from 

 incomplete examination. In their clas- 

 sic paper on the rat-prostate cytology 

 as testis hormone indicator Moore, C. 

 R., Price, D. and Gallagher, T. F., Am. 

 J. Anat., 1930, 45, 71-107 secured best 

 results after fixation in Bouin's Fluid 

 and staining with Harris' Hematoxylin 

 and Eosin. 



Swyer, G. I. M., Cancer Research, 

 1942, 2, 372-375 has checked with satis- 

 factorjf results the Schultz test for cho- 

 lesterol by chemical analyses. He has 

 also outlined a method for measuring 

 the color in the Liebermann-Burchardt 

 reaction. For singly refractile fat in 

 the epithelial cells see Gylling, P., 

 Acta Path, et Microb. Scan., 1941, 18, 

 247-258. 



To demonstrate the ducts (Le Due, 

 I. E., J. Urol., 1939, 42, 1217-1241) in 

 autopsy material lay open prostate by 

 incising length of anterior commissure 

 and express secretion from ducts by 

 gentle massage and careful sponging. 

 Locate orifices of ducts with aid of a 

 dissecting microscope. Inject celloidin 

 solution into them through No. 26 or 27 

 gauge hypodermic needle fitted with 

 tapering solder tip. Then macerate 

 with hydrochloric acid and remove all 

 except casts of the ducts. See his 

 illustrations. 



A method for demonstrating arterial 

 supply is described and illustrated in 

 some detail by Flocks, R. H., J. Urol., 

 37, 524-548. Inject internal iliac ar- 

 teries of a fresh cadaver with equal 

 parts barium sulphate and water at 200- 

 250 mm. mercury pressure. But be- 

 forehand cut small branch of superior 

 vesical artery to relieve pressure in 

 prostatic vessels. Remove prostate 

 with sufficient surrounding tissue. Cut 

 gland into 5-6 sections each about 1 cm. 

 thick. Dehydrate in ascending alco- 

 hols and clear in oil of wintergreen 

 (methyl salicylate). 



