60 PHYSIOLOGY CHAP. 



innervate the same muscles. The effect may consist in contraction 

 or in relaxation. If the plain muscle has no sympathetic innerva- 

 tion (e.g. involuntary bronchial muscles), it is indifferent to the 

 action of adrenaline. Neither the ganglion cells and nerve fibres 

 of the sympathetic, nor the muscular fibre -cells, are directly 

 attacked by adrenaline. Its action is, on the contrary, localised in 

 the end-organs, which unite the nerve fibres with the muscle 

 substance. 



These conclusions of Langley and Elliott, based on experi- 

 mental data, demonstrate clearly that there is a close connection 

 between the active principle of the suprarenal bodies (which are 

 more especially provided with chromaffine cells) and the sympathetic 

 nervous system. This tallies with the conclusions of embryology 

 and comparative anatomy, according to which, as we have seen, 

 chromaffine tissue has a common origin with the sympathetic 

 system. 



As regards the physiological action of the active suprarenal 

 principle, it must be stated in conclusion that various authors (in 

 addition to its influence on smooth muscular tissues) have ascribed 

 to it a characteristic action on metabolism. Blum (1901) noticed 

 that subcutaneous and intravenous injections of this substance 

 caused elimination of glucose by the urine. This glycosuria, 

 known also as suprarenal diabetes, was subsequently confirmed 

 and variously interpreted by other workers (Zlilzer, Crofton, Noel 

 Paton, Herter and Wakeman, Aronsohn). According to Landau 

 the substance which on injection produces glycosuria in rabbits 

 exists in the cortical and not in the medullary substance. A 

 causal relation exists between the capsule and the diabetes which 

 is produced by puncture of the fourth ventricle (01. Bernard), in 

 the sense that in some very small rabbits that survive bilateral 

 capsulectomy, puncture of the fourth ventricle does not induce 

 this diabetes. 



XVI. The discovery of the physiological action of suprarenal 

 extract stimulated the efforts of chemical physiologists to isolate 

 its active principle. Frankel (1896) first prepared sphygmogenine, 

 followed by Abel's epinephrine (1898), 0. von Flirth's suprarenine, 

 Vassale's paragangline. In 1901 Takamine announced that both 

 Abel's epinephrine and von Fiirth's suprarenine were mixtures, 

 and that he had succeeded in isolating from the suprarenal capsules 

 a stable substance that crystallises, and is of constant chemical 

 composition, to which he gave the name of adrenaline. At the 

 same time, but independently, Aldrich also isolated the active 

 suprarenal principle in a crystalline form. F. Battelli discovered 

 a more practical and improved method of preparing the same 

 substance. 



Takamine's adrenaline is a white powder, in small crystals, 

 very bitter, slightly soluble in water, faintly alkaline, so that it 



