5i6 



Pituitary and Carbohydrate Metabolism 



with that observed in hypophysectomized rats (table 5). Thus, the metabolic 

 rate and absorption rate which are similarly low in hypophysectomized rats 

 would appear to be the result of thyroid atrophy in this condition, but the 

 effects of hypophysectomy on carbohydrate oxidation would seem to be inde- 

 pendent of thyroid function. 



The effects of thyroidectomy on pancreatic and phlorizin diabetes are of 

 interest, because of the marked diminution of gluconeogenesis found after 



TABLE 6 



Insulin-Sensitivity Tests in Rats 



' Convulsions or deep coma without spontaneous recovery. 



hypophysectomy in these conditions. Thyroidectomized-depancreatized ani- 

 mals have been examined many times, with somewhat variable results. Dohan 

 and Lukens"^ have recently reinvestigated this problem carefully and shown 

 that in cats thyroidectomy reduces glycosuria and nitrogen excretion only 

 slightly— less even than might be expected due to the decrease in metabolic 

 rate. Similarly, phlorizin diabetes was early reported by Houssay" and others 

 to be but little affected by thyroidectomy. Wells and KendalP' recently com- 

 pared the effects of various procedures on the phlorizin diabetes of rats, and 

 reported that thyroidectomy produced but a barely significant decrease in 

 glucose and nitrogen elimination in this condition, the average excretion 

 rates being 15 per cent low, whereas they were 75 per cent below normal in 

 hypophysectomized rats. From these data, it appears that the failure of gluco- 

 neogenesis after hypophysectomy in pancreatic or phlorizin diabetes can be 

 the result of thyroid atrophy in small part only. However, it may be true, as 



