EFFECTS OF EXTRACTS OF PARS NEURALIS 



of a posterior-lobe extract (Molitor and Pick, 1924). Simi- 

 larly, in man water diuresis is not inhibited in certain types 

 of renal disease. From these data and from other evidence 

 it may be concluded that the antidiuretic effect of posterior- 

 lobe extract (or the vasopressor principle) is primarily on the 

 kidneys. 



The most striking therapeutic use for the diuresis-inhibit- 

 ing principle is in the treatment of diabetes insipidus. Five 



d 



z P ' 



0125456789^ 



^ Hours 



Control <2xpb., water alone. 



Water and. sabccitaneoas injection 



of posterior -lobe extract. 



Fig. 55. — The effect of posterior-lobe extract on the secretion of urine and of 

 chlorides in the urine (unanesthetized dog weighing about lo kg.) (The diagram is 

 not based on an actual experiment.) First hour: control period. At the arrow a 

 large dose of water (e.g., 75 cc. per kg. body-weight), with or without a dose of 

 posterior-lobe extract subcutaneously, is given by stomach tube. Curves: volume of 

 urine. Each 0.29 sq.cm. represents <;o cc. of urine per hour. Rectangles: total 

 chloride-excretion (millimols per hour). 



to 10 units of the vasopressor principle subcutaneously may 

 be a dose effective in an adult for 5-6 hours (Isaac and Siegel, 

 1929). No loss of sensitivity occurs in spite of the long con- 

 tinued use of the extract. A number of workers also have 

 used posterior-lobe extract for diagnostic purposes in patients 

 with primary or secondary renal disease.'' 



There is concordant evidence, which, however, sometimes 



^ Gutmann (1928); Lebermann (1928, 1930-31); Minder (1928); Hitzenberger 

 and Merkler (1929); Seelig and Voigt (1932); and others. It is usually recommended 

 that posterior-lobe extracts containing the vasopressor principle be not adminis- 

 tered to patients with a toxemia of pregnancy. 



[355] 



