METABOLISM AND THE PARS GLANDULARIS 



due to a more rapid rate of secretion on the part of the 

 pancreas. The blood of the starved hypophysectomized dog 

 has been found to cause a greater lowering of the blood-sugar 

 concentration of the rabbit than is caused by the blood of 

 the starved normal dog (Cowley, 1931; these observations 

 were not confirmed by Di Benedetto, 1934). Kepinov and 

 Guillaumie (1934) anastomosed the pancreatic vein of nor- 

 mal or hypophysectomized dogs to the jugular vein of nor- 

 mal dogs in which the adrenal veins had been tied. They 

 observed a considerable depression of the glucose-concentra- 

 tion in the blood of the recipient dog when it received pan- 

 creatic-vein blood from a hypophysectomized dog. For ex- 

 ample, I hour after transfusion had been completed (duration 

 of transfusion, 30 minutes), the blood-sugar concentration of 

 the recipient dog was 65 mg. per cent if the donor had been 

 hypophysectomized, and 90-100 mg. per cent if the donor 

 was normal. 



Although in the toad and rabbit the tolerance toward 

 glucose has been found to be increased as a result of hypo- 

 physectomy, the opposite appears often to be true of the 

 dog. In nearly all the more recent reports" the authors stated 

 that after the administration of glucose, whether by stomach- 

 tube or by injection, the concentration of blood sugar rose 

 to higher levels and returned to a normal level more slowly 

 in hypophysectomized dogs than in normal dogs. However, 

 the respiratory quotient rises after the administration of glu- 

 cose to the hypophysectomized dog (Biasotti, 1934). More- 

 over, Gaebler (1929) found no change in the basal respiratory 

 quotient of the dog after hypophysectomy. xAll these obser- 

 vations indicate that sugar-tolerance studies in the dog do 

 not support the view that hypophysectomy causes hyper- 

 insulinemia. The diminished tolerance apparently is not due 

 to interference with the oxidation of sugar. 



'° Mahoney (1934) concluded that the sugar tolerance of the hypophysectomized 

 puppy is high. 



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