162 HUMAN PHYSIOLOGY. 



with a hypertrophic condition of the bones of the face and extremi- 

 ties, to which the term acromegalia has been given. 



Intravenous injection of an extract of the hypophysis increases 

 the force of the heart-beat without any change in its frequency, and 

 causes a rise of blood-pressure from a stimulation of the arterioles 

 (Schafer and Oliver). The material secreted by the hypophysis has 

 not been isolated, hence its chemic features are unknown. After its 

 formation it probably passes through a system of ducts into the 

 cerebrospinal fluid, after which it influences the metabolism of the 

 nervous and osseous tissues as well as the force of the heart muscle. 



An extract of the hypophysis itself exerts no appreciable effect 

 on the blood-pressure or on the rate of the heart-beat, nor does 

 it influence the circulatory and respiratory organs (Howell). An 

 extract of the infundibular body intravenously injected, however, 

 gives rise to increased blood-pressure and to a slowing of the 

 heart-beat. 



Adrenal Bodies, or Suprarenal Capsules. These are two flat- 

 tened bodies, somewhat crescentic or triangular in shape, situated 

 each upon the upper extremity of the corresponding kidney, and held 

 in place by connective tissue. They measure about 40 mm. in 

 height, 30 mm. in breadth, and from 6 to 8 mm. in thickness. The 

 weight of each is about 4 gm. 



Function of the Adrenal Bodies. It was observed by Addison 

 that a profound disturbance of the nutrition, characterized by a 

 bronze-like discoloration of the skin and mucous membranes of the 

 mouth, extreme muscular weakness, and profound anemia, was asso- 

 ciated with, if not dependent on, pathologic conditions of the supra- 

 renal glands. In the progress of the disease the asthenia gradually 

 increases, the heart becomes weak, the pulse small, soft, and feeble, 

 indicating a general loss of tone of the muscular and vascular ap- 

 paratus. Death ensues from paralysis of the respiratory muscles. 

 The essential nature of the lesion which gives rise to these symp- 

 toms has not been determined. 



Removal of these bodies from various animals is invariably and 

 in a short time followed by death, preceded by some of the symp- 

 toms characteristic of Addison's disease. Their development, how- 

 ever, was more acute. From the fact that animals so promptly 

 die from extirpation of these bodies, and the further fact that the 

 blood of such animals is toxic to those the subjects of recent .extir- 



