PARATHYROID GLANDS 637 



tetany Biedl extirpated the spleen and the parathyroids it contained, and 

 the animal then developed a severe tetany within twenty-four hours and 

 died. Biedl found two parathyroid glands with their histological structure 

 well retained in the spleen after its removal. 



In several cases of transplantation of parathyroid glands into the 

 spleen, Biedl did not obtain permanent relief from tetany, the animals 

 finally dying of the disease. On postmortem examination of these ani- 

 mals, scar tissue was found at the site of implantation, the parathyroids 

 having been completely absorbed. 



Biedl further asserted that in some dogs homoiotransplantation was as 

 successful as autotransplantation. In these dogs, he first implanted into the 

 spleen parathyroid glands (two to four) from other dogs, and a few days 

 later extirpated the whole thyroid-parathyroid apparatus from the neck. 

 The animals exhibited slight symptoms of tetany at first, but then re- 

 mained for months without symptoms. The prophylaxis was not, however, 

 permanent. Similar experiments to these of Biedl have been reported by 

 Pfeiffer and Meyer, though they implanted the parathyroid glands into 

 pockets in the rectus abdominis muscle of young dogs. 



W. S. Halsted (a) (fr) (c) (d) also made a long series of experiments 

 with autotransplantation and isotransplantation of parathyroid glands in 

 dogs. In some sixty animals he transplanted parathyroid glands, using the 

 thyroid gland, the abdominal wall, and the spleen as sites for the implanta- 

 tion. Autotransplantation was successful in 61 per cent of the cases in 

 which more than half of the normal parathyroid glands had been ^previously 

 removed ; but autotransplantation did not succeed, if the reduction of the 

 dogs' own parathyroid glands had been less than this. He was never suc- 

 cessful in grafting parathyroid tissue into a dog, if the animal's own para- 

 thyroids were all intact. He found that one autotransplanted parathyroid 

 gland will entirely suffice to keep an animal in good health for months and 

 even for years (Fig. 17). But he asserts that isotransplantation of the 

 parathyroid glands in dogs invariably fails to yield grafts that live. The 

 more recent experiments of Leischner and Kohler would seem to confirm 

 these views of Halsted. 



Halsted' s studies made him skeptical, therefore, of the reported suc- 

 cesses of Biedl, since that author asserted (1) that transplantation suc- 

 ceeds even without any previous loss of parathyroid glands; (2) that sev- 

 eral parathyroid glands may by transplantation be made to grow and to 

 function; and (3) that isotransplantation of the parathyroid gland in the 

 dog is sometimes successful. 



Answering these objections of Halsted, Biedl has argued that in his 

 autotransplantation there is, in reality, a lack of functioning parathyroid 

 gland at least for a time, namely, for the period that elapses between the 

 time the parathyroid tissue is implanted into the spleen and the time it 

 becomes vascularized. Biedl grants that parathyroid grafts grow more 



