970 THE INTERNAL SECRETIONS 



months by an active proliferation. In this connection, it should also 

 be mentioned that the results obtained by the feeding of extract of 

 adrenal gland to animals whose adrenals had been removed, have 

 not been encouraging. Moreover, in only a few cases has this type 

 of organotherapy been of any use in relieving the symptoms of Addi- 

 son's disease. 



The General Function of the Adrenal Glands. — While the effects 

 of total and partial extirpation of the adrenals clearly proved that 

 these organs furnish an active principle which is absolutely essential 

 to life, the nature of this internal agent was not revealed until the 

 time of Oliver and Schafer.^ These investigators made an extract 

 of this gland and injected it into the venous blood-stream. A rise 

 in blood-pressure invariably resulted which was correctly referred by 

 them to a constriction of the blood-vessels. Further experimentation 

 then showed that this vasoconstrictor agent is a product of the medulla 

 and not of the cortex of this gland. Nothing definite, however, 

 could be learned regarding the function of the latter, although it was 

 surmised that its loss gives rise to a decided muscular weakness (as- 

 thenia) of the skeletal muscles, coma, and convulsions. The evidence 

 which has been presented in favor of this view, is chiefly indirect 

 in its character and is based upon the following data: 



(a) The symptoms just cited cannot be mitigated by the repeated or continuous 

 administration of extracts of the medulla, in the form of epinephrin or adrenalin. 



(b) It has been shown by Stewart that the discharge of epinephrin into the 

 circulation ceases immediately after the removal of one adrenal body and the 

 denervation of the other. This procedure, however, does not prove fatal to the 

 animal. 



(c) No beneficial results have been obtained so far by treating Addison's 

 disease with adrenalin which is a product of the medulla. 



(d) Those animals which are in possession of "accessory" adrenals in the form 

 of separate chromaffin-bodies (rabbits), do not die after the removal of the adrenal 

 glands, and 



(e) It has been found that transplanted adrenals exhibit a degeneration of their 

 medulla and a proliferation of their cortex. 



It will be remembered that these animals develop no untoward symp- 

 toms. Thus, it cannot be doubted that the internal agent of the cor- 

 tex is different from that of the medulla. While the former furnishes 

 a still obscure product, the absence of which gives rise to the grave 

 symptoms mentioned above, the latter gives rise to epinephrin. ^ 

 Epinephrin. — The extract of adrenal gland employed by Ohver and 

 Schafer,^ was obtained by simply lacerating and pounding the adrenal 

 tissue in a mortar under a 0.7 per cent, solution of sodium chlorid.^ 



1 Jour, of Physiol., xxviii, 1895, 230. 



2 Vincent, Endocrinology, i, 1917, 140, and Schafer, The Endocrine Organs, 

 London, 1916. 



3 A year later Cybulski and Szymonowicz published the results of a series of 

 independent experiments of similar nature (Pro. Acad, of Krackau, 1895). 



^ In 1856 Vulpian isolated a substance from the adrenal gland which showed 

 remarkable color reactions (Compt. rend., xliii, 1856). 



