274 THE INTERNAL SECRETIONS 1920 



marked the exhibition by both of vasomotor excita- 

 bility, dermographism, urticaria and transient edemas. 

 Anaphylaxis is known to be produced by the entrance 

 into the general circulation of protein matter foreign 

 to the human body. 6 It is not definitely known to be 

 due to anything else, yet similar symptoms actually 

 occur in hyperthyroidism. 



That excess amounts of thyroid secretion in the 

 general circulation may be one immediate cause of 

 certain urticarias and transient edemas (i. e., anaphy- 

 lactic-like symptoms) would therefore, on first thought, 

 appear to be plain. Yet it must be recalled that the 

 phenomena under consideration are definitely localized 

 vasoconstrictions ; and that the function of vasocon- 

 striction belongs not to the thyroid gland or its secre- 

 tion, but to the involuntary nervous system and the 

 thyroid antagonists, i. e., the posterior lobe of the 

 hypophysis and the adrenal medullary tissue or chro- 

 maffin system. Thyroid secretion per se, if in excess, 

 actually produces vasodilation, and not vasoconstric- 

 tion. On second thought, therefore, we are convinced 

 that the thyroid cannot alone cause urticarias and 

 transient edemas, but that its antagonists may do so 

 under certain conditions. 



It is, therefore, plain that a classification of the va- 

 rious forms of urticaria simply as vasomotor neuroses 

 does not go quite far enough. A disease whose prin- 

 cipal symptom is a localized vasoconstriction cannot 

 be regarded solely as a disorder of the nervous sys- 

 tem, when at least two different ductless glands are 

 known to produce internal secretions which possess 

 a marked capacity to bring about vasoconstriction. 

 Definite doubts consequently arise as to whether either 

 of the nervous systems plays more than its usual role 

 that of conductor of impulses only in disorders of 

 this type. Furthermore, it is difficult to conceive how 

 anaphylaxis, recognized as the result of a foreign pro- 



