Electrophysiology of the Glands 197 



will continue to be widely adopted because of their apparent 

 simplicity and because of the long tradition going back to Heiden- 

 hain and Merkel which has hallowed them. 



We have not attempted in the rest of this chapter to undertake 

 a comparison of salivary secretion with that of other glands be- 

 cause, although there are obvious similarities in the ground plan 

 of most secreting glands, so little is known of secretion in these 

 other structures. 



ELECTROPHYSIOLOGY OF THE SALIVARY GLANDS 



It was originally found by Bayliss and Bradford (1885) that a 

 potential difference appeared between an electrode placed on the 

 convexity of the submaxillary gland and one placed on the hilus 

 when secretion was produced by stimulation of the chorda tym- 

 pani. It was quickly established that this potential was not due to 

 a change in blood flow because amongst other experiments, the 

 administration of atropine in a dose sufficient to abolish secretion 



; 10 1 Cat submaxillary electrogram in response to chorda stimulation. 

 One electrode was placed on the gland convexity and the other close to the 

 hilus. 

 Hilus positivity corresponds to an upward deflection on the "cord. The i^^^ successive 

 ones from the same gland, showing the great variation in response (Lundberg, IQ55). 



