ADRENALECTOMY 151 



of the organs was allowed to remain, the birds survived for 15 

 days. The adrenals in birds are so situated as to make the 

 operative approach exceedingly difficult. Subsequent workers 

 have consequently avoided the use of birds although much of 

 interest might be learned by studying the effects of adrenalec- 

 tomy in this species. 



Gourfein extirpated the glands through an incision ex- 

 tending obliquely from the caudal tip of the sternum to the 

 ischium. His birds recovered from the operation but soon 

 began to manifest muscular weakness and died usually within 

 a few hours. 



Rat and mouse. The advantages and ready availability of 

 the rat (Mus norvegicus) as an experimental animal have 

 made it the subject of many studies on the effects of adrenalec- 

 tomy. The older view that the rat differs from other mammals 

 in being able to withstand the effects of adrenalectomy due 

 to the presence of widespread accessory tissue has been thor- 

 oughly disproven in recent years. Jaffe 332 showed that of 90 

 adrenalectomized rats, 35 per cent died within 30 days of the 

 operation, the majority dying before the 13th day, with the 

 typical symptoms of acute adrenal insufficiency. Forty-six 

 per cent showed chronic insufficiency and died within seven 

 months without the presence of gross accessories being mani- 

 fested at autopsy. In the remaining 19 per cent, which were 

 unaffected by the operation, large accessory cortical bodies 

 were found at autopsy. Pencharz, Olmsted, and Giragos- 

 sintz 491 proceeded further in their analysis and concluded that 

 the rat is no exception to the rule that insufficiency and death 

 invariably follow a complete adrenalectomy. In 62 rats 

 death occurred in from two to eighteen days with no survivals. 

 If only 5 per cent of the gland were left at operation, rapid 

 regeneration occurred and the animal survived. Subsequent 

 workers 198 have confirmed these results and demonstrated that 

 the rat is no exception to the general rule that adrenalectomy 

 is fatal. Survival is due to incomplete extirpation, which 



