SECRETION. 271 



power of forming a specific organic compound of iodine, and it is possible 

 that its influence upon body-metabolism may be connected with this feet 

 Baumann and Koos ' state that the iodothyrin is contained within the gland 

 mainly in a state of combination with proteid bodies, from which it may be 

 separated by digestion with gastric juice or by boiling with acids. Most of 

 'the substance is combined with an albuminous proteid, while a smaller part 

 is united with a globulin-like proteid. There can be little doubt that 

 the authors have succeeded in isolating at least one of the really effective 

 substances of thyroid extracts. If the distinction made between the functions 

 of the thyroids and parathyroids proves to be correct, and if each of these 

 glands exercises its functions by means of an internal secretion, we may hope 

 that future work will be able to isolate the distinctive substance or Hill- 

 stances characteristic of each gland. 



Adrenal Bodies. — The adrenal bodies — or, as they are frequently called 

 in human anatomy, the suprarenal capsules — belong to the group of ductless 

 glands. Their histology as well as their physiology is incompletely known. 

 It was shown first by Brown-Sequard (1856) that removal of these bodies is 

 followed rapidly by death. This result has been confirmed by many experi- 

 menters, and so far as the observations go the effect of complete removal is 

 the same in all animals. The fatal effect is more rapid than in the case of 

 removal of the thyroids, death following the operation usually in two to three 

 days, or, according to some accounts, within a few hours. The symptoms 

 preceding death are great prostration, muscular weakness, and marked dimi- 

 nution in vascular tone. These symptoms are said to resemble those occurring 

 in Addison's disease in man, a disease which clinical evidence has shown to be 

 associated with pathological lesions in the suprarenal capsules. It has been 

 expected, therefore, that the results obtained for thyroid treatment of myx- 

 cederna might be repeated in cases of Addison's disease by the use of adrenal 

 extracts. These expectations seem to have been realized in part, but complete 

 and satisfactory reports are yet lacking. The physiology of the adreuals has 

 usually been explained upon the auto-intoxication theory. The death that comes 

 after their removal has been accounted for upon the supposition that during 

 life they remove or destroy a toxic substance produced elsewhere in the body, 

 possibly in the muscular system. Oliver 2 and Sehaefer, and, about the same 

 time, Cybulski and Szymonowicz, 8 have given reasons for believing that this 

 organ forms a peculiar substance that has a very definite physiological action 

 especially upon the circulatory system. They find that aqueous extracts of 

 the medulla of the gland when injected into the blood of ;i living animal 

 have a remarkable influence upon the heart and blood-vessels. If the vagi 

 are intact, the adrenal extracts cause a very marked slowing of the heart-beat 

 together with a rise of blood-pressure. When the inhibiting fibres of the 

 vagus arc thrown out of action by section or by the use of atropin the beart- 



1 Zeitschrift fur physiologisehe Chemie, L896, Bd, xxi. S. 481, 



* Journal of Physiology, 1895, vol. xviii. |>. 'J.'lu. 



3 Archir fiir die geeammte Physiologic, L896, Bd. Ixiv. S. !)7. 



