PHYSIOLOGY AND EXPERIMENTAL PATHOLOGY 103 



dred and thirty-eight hours. Cats, rabbits, rats, mice and frogs lived 

 usually a day or two. 



Still greater improvement in technique has established beyond a 

 doubt that the symptoms produced are due to a loss of the glands and 

 not to trauma incident to the operation. BiedFs method of suprarenal 

 extirpation offers unquestionably the best means of avoiding complications 

 due directly to the operation. He first dislodged the suprarenals in a dor- 

 sal direction through lumbar incisions. Leaving the glands attached 

 by means of the blood vessels he sewed them in between the skin and the 

 musculature. No ill effects were observed. Three or four days later 

 the glands were exposed by cutting through the skin and then removed 

 after the blood vessels were ligated. The results of his experiments con- 

 firmed the conclusions that the suprarenals are essential to life. 



One of the greatest stumbling blocks in the solution of the suprarenal 

 problem has been the work on the rat. It had been shown, that some 

 individuals could survive extirpation of both glands. This raised the 

 suspicion in the minds of many that perhaps these structures are not 

 so important after all. 



This question of the value of the suprarenal in the life of a rat was 

 revived by the work of Boinet (a). He found that six out of forty-eight rats 

 survived longer than five months and were in perfect health after double 

 epinephrectomy. In answer to the criticism of Abelous and Langlois 

 that these survivals might be explained by the presence of accessory supra- 

 renal tissue, Boinet (c) removed both suprarenals and such accessory supra- 

 renals as he could find in twelve rats. Seven animals recovered. He 

 claimed, therefore, that the role of accessory tissue in decapsulated rats 

 was exaggerated. 



Boinet stated that he removed the supplementary glands situated at 

 the junction of the renal veins or along the border of the posterior sur- 

 face of the kidneys. However, Wiesel has found accessory cortical bodies 

 between the testicles and the lower pole of the epididymis. These evi- 

 dently were not excised by Boinet and supposedly account for his nega- 

 tive results. At any rate the rat does not give the clear cut evidence 

 which we desire. Those animals which do survive double capsulectomy 

 must possess a larger amount of accessory tissue than usual. Occasionally 

 other species survive a similar operation but the percentage of subjects 

 that survive seems to be related to the proportion of accessory tissue pres- 

 ent. The guinea pig, on the other hand, which rarely ever (Velich(c) ) pos- 

 sess accessory cortical tissue seldom survives double epinephrectomy. 



Compensatory Hypertrophy of Suprarenal Tissue. Not only does the 

 presence of accessory tissue play an important part in the mainte- 

 nance of life after removal of suprarenal tissue but the hypertrophy of 

 this tissue as well as of portions of the suprarenal left in situ may lead 

 to permanent recovery, or at least postpone the fatal result. 



