THE SUPRARENAL SYSTEM 173 



The value of the experiments of v. Haberer and Stoerk, which 

 will be described more fully later, lies in the proof which they 

 supply that the suprarenal may be transplanted with success, both 

 functional and anatomical, provided its vascular stem is left 

 intact. Further, these experiments were the first to show that, 

 after transplantation, the medullary substances lives and becomes 

 hypertrophied in exactly the same manner as the cortical sub- 

 stance. The conclusion drawn by the authors from these findings, 

 namely, that the part played by the medulla in suprarenal function 

 is of equal importance with that of the cortex, is the more in- 

 controvertible seeing that other observations have supplied proof, 

 not only of the vital necessity of the medulla, but also of its 

 functional significance. But, in my opinion, the successful trans- 

 plantations of v. Haberer and Stoerk are decided evidence against 

 the view, that the medulla is the only part of the suprarenal capsule 

 which is essential to life. This theory was based upon experiments 

 where transplantation, though technically successful, was followed 

 by death, and it depended upon the fact that degeneration of the 

 medullary substance, together with preservation of the cortex, were 

 always found in such cases. All that these older experiments prove, 

 however, is the greater sensibility and lability of the medulla. 

 They show, and this is confirmed in other directions, that a 

 reduction in the vascular provision and a limitation of the nutri- 

 tional conditions invariably kills the medulla, but that the cortex 

 has greater powers of resistance. 



Free grafting of chromaffine tissue is successful in those cases 

 only where this tissue is normally situated upon a free surface 

 as, for instance, the dorsal surface of the kidney in reptiles 

 (Christiani's experiments with lizards). Parodi's experiments 

 show that embryonal suprarenal tissue, in which the medulla lies 

 upon the surface, possesses very little regenerative power ; and, 

 in an experiment recently described by Neuhauser, the trans- 

 plantation of embryonal tissue into the kidney of a rabbit was 

 followed by a tumour-like growth. 



The results of experimental transplantation, as far as they go 

 to-day, not only prove the internal secretory function of the supra- 

 renals and their vital importance to the organism, but they also 

 justify the hope that the clinical symptoms produced by supra- 

 renal suppression may be more successfully treated by surgical 

 means than has been possible, up to now, by organo-therapeutic 

 measures. 



THE ACTIVITY OF SUPRARENAL EXTRACT. 



Investigation of the clinical activity of extract of the supra- 

 renals, has effected a clearer insight into the function of these 

 organs. 



As early as 1879, Pellacani demonstrated the toxic action of 



