THE SUPRARENAL SYSTEM 2OQ 



present, then, the innervation of the bronchial muscles is 

 autonomous in the sense of motor stimulation, while the presence 

 of a sympathetic innervation has not, up to now, been demon- 

 strated. From Dixon and Brodie's careful experiments, it seems 

 as if suprarenal extract exercised very little effect upon the 

 bronchial muscles. Small doses do not produce either contraction 

 or expansion of the bronchioles, while large doses have been 

 followed in isolated cases by transient contraction. These 

 findings are confirmed by my own experiments with adrenalin. 

 In anaphylactic shock (Auer and Lewis) in guinea-pigs, as well 

 as after the intravenous injection of peptone (Biedl, Kraus), there 

 is acute cramp of the bronchial muscles which is promptly 

 relieved by atropine, the action of which is to paralyse the vagus. 

 In cases such as these, the intravenous injection of adrenalin is 

 negative in its result. According to Jagic, bronchial asthmatic 

 spasm in man may be checked by the subcutaneous injection of 

 i c.cm. adrenalin. Eppinger and Hess explain this result by the 

 assumption, that the stimulation of the sympathetic by adrenalin 

 overpowers the muscular cramp arising from the increased stimu- 

 lation of the vagus. In view of these divergent findings, 

 further investigation of the innervation conditions of the 

 bronchial muscles and of the effect which adrenalin has on them, 

 appears to be imperative. 



The Eye. The intravenous injection of adrenalin provokes 

 retraction of the nictitating membrane, elevation of the eye-lid, 

 exophthalmos, and dilation of the pupil. Thus, the musculus 

 palpebras tertius, the unstriated muscles of the eye-lid, the 

 musculus protrusor bulbi, and the musculus dilatator pupillas, are 

 all induced to contract in the same manner as after electric stimula- 

 tion of the sympathetic nerve in the region of the neck. 

 Adrenalin produces effects which are similar and even more 

 powerful, after extirpation of the superior cervical ganglion and 

 consequent degeneration of the post-ganglionary fibres (Lewand- 

 owsky, Langley). It seems certain from this that the site 

 directly affected by adrenalin is peripheral. 



The effect which adrenalin has in enlarging the pupil was 

 next studied, and from two points of view. In the first place, it 

 has been turned to account as a test for adrenalin and as a 

 method of determining its physiological significance. Wesseley, 

 and later Meltzer and Auer, found that, when applied to the eyes 

 of frogs, adrenalin produced mydriasis, and the latter authors 

 suggested (1904) the frog's eye as a suitable adrenalin reagent. 

 They pointed out that the reaction takes place even after enu- 

 cleation of the bulb. Ehrmann next showed that, when preserved 

 in isotonic fluid, the enucleated frog's eye is considerably more 

 sensitive than the bulb in situ, and upon these findings he based 

 his quantitative adrenalin test. Ehrmann found that adrenalin 

 reacts upon the dilator muscles of the pupil in a solution of i :2O 



14 



