182 THE DUCTLESS GLANDS 



after the superior cervical ganglion has been excised and the 

 nerve fibres from it have degenerated. With regard to somatic 

 muscle, Langley is inclined to accept Lewandowsky's view, 

 while in the matter of plain muscle he is content (in the paper 

 of 1901-02) with the generalization that the effect of adrenin 

 is the same as the effect of exciting the sympathetic nerves 

 supplying the particular tissue. 



In studies on the action of adrenin on the bloodvessels of 

 the rabbit's ear Meltzer and Auer showed that section of the 

 sympathetic has a marked effect on the results of intravenous 

 injection of the drug. While on the normal side the constric- 

 tion of the vessels reaches its maximum in a few seconds, on 

 the side of the section it lasts a very long time, and is very 

 pronounced. Following up the discovery of Lewandowsky 

 (confirmed by Boruttau and Langley), that intravenous 

 injection of adrenin induces a temporary dilation of the pupil, 

 Meltzer and Auer found that, though subcutaneous injection 

 and conjunctival instillation produce no effect in the normal 

 animal or after section of the cervical sympathetic, yet such 

 administration produces very striking dilation of the pupil 

 after removal of the superior cervical ganglion that is to say, 

 "the paradoxical effect" is marked in the case of adrenal 

 extract. 1 



These observations were confirmed and extended by Elliott, 

 who generalized as follows : " This, then, is true for all the 

 muscles thrown into contraction by adrenalin, that after 

 decentralization i.e., degenerative section of the preganglionic 

 sympathetic nerves and still more clearly after denervation 

 (degenerative section of the post-ganglionic sympathetic 

 nerves), they contract in the presence of adrenalin alike with 

 greater irritability and persistence." Elliott concluded as to 

 the localization of the action of adrenin that the excitation 

 must be due to some substance within the muscle fibres being 

 affected by the drug, and suggested that this substance is 

 present at the " myoneural junction," where it is originally 

 formed. 



1 Meltzer and Auer point out an important difference between mammals 

 (rabbits and cats) and the frog. In the latter animal in a normal state, 

 subcutaneous injection or instillation into the conjunctival sac produces in a 

 few minutes a characteristic dilation of the pupil, which may last for hours, 

 so that the frog has become a convenient means of testing adrenal extracts. 





