1. The hypophysectomized cat shows an alleviation of the diabetes following pancreatectomy comparable to that previously demonstrated by others in the dog.
2. It is possible by various procedures to remove both adrenals and all the pancreas from cats. Such animals have survived for as long as 4 weeks without the use of insulin, the average survival being 18 days. Daily injections of cortical extract are necessary. By contrast, cats deprived of insulin by similar procedures but with adrenals intact survive only 4–5 days.
3. Adrenalectomized-depancreatized cats show as striking an alleviation of the diabetes as do those hypophysectomized and depancreatized. This is expressed by the markedly decreased glucose, nitrogen and acetone body excretion compared to that found in the depancreatized cat, as well as by the increased survival period.
4. Removal of epinephrine by denervation or demedullation of the adrenals does not protect against pancreatic diabetes in the cat.
5. The carbohydrate tolerance of depancreatized cats is not significantly increased by hypophysectomy or adrenalectomy.
The exceptions to this finding have all been in animals presenting varying degrees of spontaneous hypoglycemia.
6. It is our opinion that the effects of hypophysectomy or adrenalectomy upon pancreatic diabetes are due to diminution of the production of glucose and acetone bodies rather than to the resumption of normal carbohydrate utilization.