VASCULAR OR DUCTLESS GLANDS. 147 



muscular weakness, and profound anemia, was associated with, if not de- 

 pendent on, pathologic conditions of the suprarenal capsules. 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 mus- 

 cular and vascular apparatus. Death ensues from paralysis of the respira- 

 tory muscles. The essential nature of the lesion which gives rise to these 

 symptoms 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 symptoms character- 

 istic of Addison's disease. Their development, however, 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 sub- 

 jects of recent extirpation, but not to normal animals, the conclusion was 

 drawn that the function of the adrenal bodies was to remove from the blood 

 some toxic material the product of muscle metabolism. Its accumulation 

 after extirpation gives rise to death through auto-intoxication. 



On the supposition that the adrenals might secrete and pour into the blood 

 a specific material which favorably influences general metabolism, Schafer 

 and Oliver injected hypodermically glycerin and water extracts, and observed 

 at once an increased activity of the heart-beats and of the respiratory move- 

 ments. The effects, however, were only transitory. When these extracts 

 are injected into the veins directly, there follows in a short time a cessation 

 of the auricular contraction of the heart, though the ventricular contraction 

 continues with an independent rhythm. If the vagi are cut previous to the 

 injection or if the inhibition is removed by atropin, the rapidity and vigor 

 of both auricles and ventricles are increased. Whether the inhibitory in- 

 fluence is removed or not, there is a marked increase in the blood-pressure, 

 though it is greater in the former than in the latter instance. This is attri- 

 buted to a direct stimulation and contraction of the muscle-fibers of the arteri- 

 oles themselves, and not to vaso-motor influences, as it occurs also after 

 division of the cord and destruction of the bulb. The contraction of the 

 atterioles is quite general, as shown by plethysmographic studies of the limbs, 

 spleen, kidney, etc. Applied locally to the mucous membranes, the adrenal 

 extract produces contraction of the blood-vessels and pallor. The skeletal 

 muscles are affected by the extract very much as they are by veratrin. The 

 duration of a single contraction is very much prolonged, especially in the 

 phase of relaxation or of decreasing energy. 



It is evident from these experiments that the adrenal bodies are engaged 

 in elaborating and pouring into the blood a specific material which stimulates 

 to increased activity the muscle-fibers of the heart and arteries, and thus 

 assists in maintaining the normal blood-pressure as well as the tonicity of 



