1904.] Joining Cervical Sympathetic with Chorda Tympani. 99 



" On the Effects of Joining the Cervical Sympathetic Nerve with 

 the Chorda Tympani." By J. K Langley, F.K.S., and 

 H. K. Anderson, M.D. Eeceived January 26, — Eead 

 February 4, 1904. 



It is well known that the cervical sympathetic nerve and the chorda 

 tympani have opposite actions upon the blood-vessels of the sub- 

 maxillary gland, the former causing contraction of the vessels, and 

 the latter, dilatation. Evidence has been given by one of us* that the 

 chorda tympani if united with the cervical sympathetic, can in time 

 make connection with the nerve cells of the superior cervical 

 ganglion and become in part vaso-constrictor fibres. Our experiments 

 have been directed to determine whether the cervical sympathetic if 

 allowed an opportunity of becoming connected with the peripheral 

 nerve cells in the course of the chorda tympani will in part change 

 their function from vaso-constrictor to vaso-dilator. Two experiments 

 were made on anaesthetised cats, both give similar results, but one 

 was much more conclusive on the point at issue than the other, and 

 here we shall speak of that only. The superior cervical ganglion was 

 excised and the central end of the cervical sympathetic nerve was joined 

 to the peripheral end of the lingual, which contains the chorda tympani 

 fibres. After allowing time for union and regeneration of the nerves, 

 the cervical sympathetic was stimulated ; it caused prompt flushing 

 of the sub-maxillary glands, and the effect was repeatedly obtained. 



The experiment shows we think (1) that vaso-constrictor nerve 

 fibres are capable of making connection with peripheral vaso-dilator 

 nerve cells, and becoming vaso-dilator fibres, and (2) that whether 

 contraction or inhibition of the unstriated muscle of the arteries occurs 

 on nerve stimulation, depends upon the mode of nerve-ending of the 

 post-ganglionic nerve fibre. 



The cervical sympathetic gave a less scanty and more prolonged 

 secretion than normal, so that some of its nerve fibres had become 

 connected with the peripheral secretory nerve cells of the chorda 

 tympani. 



A full account will be published later in the ' Journal of Physiology.' 

 * Langley, ' Journal of Physiology,' 1898. vol. 23, p. 267. 



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