PARS NEURALIS AND INTERNAL SECRETION 



injection caused an average elevation of 15 mm. Hg in the 

 systolic blood pressure; only rarely were symptoms other 

 than paleness of the face and cyanosis of the lips present. 

 These observations suggest that the diminished response of 

 pregnant women to the vasopressor principle is due to a sub- 

 stance liberated into the blood. Whether or not a disturbance 

 in its formation may be etiologically important in eclampsia, 

 as Schockaert and Lambillon suggest, is unknown. 



The experiments of Anselmino and Hoffman were the basis 

 for the attractive hypothesis that the reduced urinary secre- 

 tion and the hypertensive symptoms of certain diseases such 

 as eclampsia and essential hypertension are due to a "hyper- 

 vasopressinemia." However, satisfactory confirmatory data 

 are almost entirely lacking. Dieckmann and Michel (1937) 

 as well as others have pointed out that the pregnant woman 

 in the pre-eclamptic condition is markedly hypersensitive to 

 the pressor effect of pars neuralis extract; moreover, they 

 concluded that this abnormal response constitutes a useful di- 

 agnostic test for pre-eclampsia, but that it is not free from 

 danger. Byrom (1938) has suggested that abnormally large 

 amounts of free oestrin may circulate in the blood of patients 

 with eclampsia and that this oestrin synergizes with vaso- 

 pressor hormone in causing the important pathological 

 changes (see pp. 263-64). According to Coester (1935), puri- 

 fied extracts of urine from normal individuals or from patients 

 with two varieties of hypertension produced about the same 

 diuresis-inhibiting and pressor effects. Still other observa- 

 tions have been made by Jores (1936), who concluded that 

 abnormal amounts of anterior pituitary hormones stimulat- 

 ing the adrenals (cortex and medulla) circulate in the blood 

 in certain hypertensive disorders, such as essential hyper- 

 tension and pituitary basophilism (Gushing), and that these 



and others which have been made before indicate that man, Hke other animals, 

 exhibits a clear-cut pressor response to intravenous injections of pars neuralis ex- 

 tracts. 



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