ASSAY OF CORTICAL HORMONE 255 



The left adrenal in the rat lies superficially, just anterior to 

 the kidney. It comes readily into view when the incision in the 

 lumbar muscles is held open by spreading the forceps. 



In order to perform a complete extirpation of the glands in 

 the rat, it is essential to avoid grasping the gland or its capsule. 

 The gland is very friable and it is an easy matter to leave a bit 

 of the capsule attached to which is a thin layer of cortical cells. 

 These if left in the body multiply and may maintain the 

 animal alive indefinitely, particularly after a short period of 

 therapy with salt or the cortical hormone. The microscopic 

 nests of accessory bodies are present in the veil of loose connec- 

 tive tissue which surrounds the adrenals. This veil of mesen- 

 tery must therefore be removed together with the main gland 

 by making a wide excision of the connective tissue surrounding 

 the glands. This is easily done by using a curved forceps with 

 which one grasps the pedicle of the gland and thereby includes 

 the above mentioned mesentery which contains any accessory 

 cortical tissue. Should it be necessary to grasp the gland more 

 securely, this is done by applying a second forceps proximal to 

 the first. The adrenal is now gently brought forward and the 

 pedicle is cut with a scissors leaving the gland and its attached 

 connective tissue in the grasp of the forceps. 



The right adrenal is situated somewhat more anteriorly than 

 the left and it is covered by the liver. Its removal is therefore 

 somewhat more difficult to effect. The incision through the 

 muscles should be made along the costal margin by the method 

 described for the left gland. This incision is held open with a 

 straight forceps while the kidney is gently depressed with the 

 curved forceps. The adrenal is then seen lying anteriorly to 

 the kidney and covered by a lobe of the fiver. While the 

 gland is kept in view by depressing the kidney, the forceps is 

 projected and is made to embrace the gland and its surrounding 

 connective tissue as in extirpating the left gland. By gentle 

 traction the gland is raised, and the pedicle is cut. 



The incisions in the lumbar muscles, which should be about 



