9» 



Spontaneous Secretion of Saliva 



Section of Moussu's nerve in the sheep was found to diminish but 

 not abolish the flow; a constant flow of about 0-3 ml. per minute 

 was maintained. This was the case after section of the cervical 

 sympathetic, facial and auriculo-temporal nerves, or after large 

 doses of atropine given into the carotid artery. Likewise, there 

 was a secretion after evisceration and from a perfused gland. 

 Fig. 5.2 shows that the continuous flow can be increased -reflexly 

 or by stimulation of Moussu's nerve and is reduced to a low, 

 constant level by denervation. 



Whether there is a spontaneous secretion of saliva in human 

 beings is difficult to state. A continuous flow between meals has 



9 1 



8 



7 



6 



5 



4 





^3 



^ 2 



7 s 1 

 * 



Fig. 



Control 

 (intact nerves) 



left 



1133 



Stimulate left 

 Moussu's nerve 



Cut left 

 Moussu's nerve 

 -6V stimulation 

 tongue 



Right Left 



Cut left 

 Moussu's nerve 



Cut left 

 Moussu's nerve 



Right 



12.07 



5.2. The rate of saliva flow from the right and left parotid glands of a 

 sheep under cyclopropane anaesthesia. 

 (Coats, Denton, Coding and Wright, 1956.) 



often been reported. Lashley (191 6), for instance, usually observed 

 a secretion from the parotid gland, although in some subjects, 

 when particularly quiet, the flow ceased for some minutes. The 

 term "resting secretion" has been used to mean a secretion which 

 occurs in the absence of any obvious external stimulus (Spealman, 

 1943). It is clearly difficult to exclude the reflexly evoked secretion, 

 caused by the devices used to collect the saliva. Observations on 

 patients with an accidental fistula of the salivary duct are, there- 

 fore, of particular interest. In such persons Zebrowski (1905) 

 found no secretion from the parotid gland between meals. He 

 quotes an observation by Mitscherlich (1832) according to which 

 a patient with a parotid fistula had a very scanty flow of saliva 



