CHAPTEK IX 

 THE SUPRARENAL CAPSULES (continued) 



Effects of Suprarenal Removal: Epinephrectomy 



Addison's account of the disease he described and which he termed 

 idiopathic ancemia led Brown-Sequard to test the effect of the removal 

 of the suprarenal glands in animals. The operation, which was performed 

 upon a number of animals of different species (rabbits, guinea-pigs, dogs, 

 and cats), was followed in every case of double extirpation by a fatal 

 termination within thirty-seven hours of the removal. But a fatal result 

 was produced also in all or nearly all the animals in which the lesion was 

 unilateral, although subsequently Brown-Sequard succeeded in keeping 

 some animals alive for a few days when only one capsule was removed. 

 Since it is now well established that careful removal of one capsule under 

 aseptic precautions is not fatal, 1 there can be little doubt that Brown- 

 Sequard's results were in considerable measure the consequence of shock 

 and sepsis, and that they could not be relied on as a proof that the 

 suprarenal capsules are essential to life. This is indeed the opinion which 

 was formed by most of his contemporaries. Nevertheless, looked at in 

 the light of our present knowledge, it is certain that death must have 

 been either caused or greatly accelerated by the removal of both capsules — 

 since this is now known to be in most animals the invariable result of the 

 double operation and to occur within a few days. There are, however, 

 exceptions, especially in some species of animals : among which the 

 white rat may be particularly mentioned. These exceptions are probably 

 associated with the occurrence of accessory bodies, but whether these must 

 be of cortical or medullary nature — or both — is not determined. 



No effect of the extirpation — especially if the operation is performed 

 on the two glands at an interval of a few days — is at first apparent. For 

 some days there is little sign of anything wrong. Presently the animal 

 becomes less lively and exhibits signs of muscular weakness. The body 

 temperature also becomes lowered, but the blood-pressure is fairly main- 

 tained. Ultimately the weakness becomes extreme, the pulse feeble, the 

 blood-pressure low, and the respiration dyspnceic. Death soon follows, 

 sometimes immediately preceded by convulsions. 



1 An exception must be made for the guinea-pig, in which unilateral extirpation is 

 frequently followed by death. It may be remarked that the suprarenals of the guinea-pig 

 are larger in proportion to its size than are those of any other animal. 



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