CHAPTER IV. 



THE INTERNAL SECRETIONS OF THE THYROID AND 



THYMUS GLANDS IN THEIR RELATIONS 



TO THE ADRENALS. 



THE THYROID GLAND AND THE ADRENALS. 



A FEW years ago Robert Hutchinson 1 closed a review of 

 the literature upon the effects of thyroid extractives on 

 metabolism with the following remark: "Briefly, then, it may 

 be said that the effect of the administration of the thyroid is 

 to increase oxidation in the body; it makes the tissues, as it 

 were, more inflammable, so that they burn away more rapidly. 

 The products of the disintegration of the nitrogenous tissues 

 appear in the urine almost entirely in the form of urea, uric 

 acid, the xanthin bases, being neither regularly nor appreciably 

 increased, while the products of the fat-destruction are elimi- 

 nated as C0 2 by the lungs, and water by the kidneys." Recent 

 investigations have but confirmed these deductions. 



On the other hand, there is considerable uncertainty in 

 respect to the physiological role of the thyroid. This is well 

 exemplified in the following lines by Professor Foster 2 : "When 

 in certain animals (monkeys, dogs, and other carnivora* ; and 

 the same has been observed in man) the gland is extirpated, 

 even with the greatest care, the operation is frequently fol- 

 lowed by the occurrence of peculiar nervous symptoms, such 

 as muscular twitching* and tremors, spasms, and even tetanic 

 convulsions (more especially observed in young animals), ac- 

 companied or succeeded by irregularity or failure of voluntary 

 movements; subsequently there may ensue varied symptoms 

 which may be described under the general term of disordered 

 nutrition, ending eventually in death. In a certain number of 

 cases, however, in the above kinds of animals, no serious 

 symptoms follow, even the total extirpation of the organ pro- 



1 Robert Hutchinson: British Medical Journal, July 16, 1898. 



2 Foster: Loc. cit., 465. 



8 The italics are our own. 



(146) 



