CHAPTER II 

 THE ANATOMY OF THE SALIVARY GLANDS 



The gross anatomy of the salivary glands and their nerve supply 

 is adequately described in the standard textbooks of anatomy, and 

 the experimental preparation of the submaxillary and sublingual 

 glands in Liddell and Sherrington (1923). The only description of 

 the approach to the parotid innervation is that given by Heiden- 

 hain (1883). In the dog the postganglionic nerve (auriculo-tem- 

 poral) can be reached more satisfactorily along the inner side of the 

 ramus of the mandible after retraction of the mylohyoid and the 

 tongue and division of both pterygoid muscles (Burgen, 1955). 



Histologically the salivary glands are composed of acini, a tubule 

 system and excretory ducts. Between the acini and the main excre- 

 tory ducts there are usually at least two kinds of epithelium lining 

 the ducts. In rodents the ducts are a more prominent feature of the 

 gland histology than are the acini. If custom had not hallowed the 

 use of the term duct for these intermediate structures in the gland, 

 tubule would be more descriptive, for these structures are probably 

 at least as important in the secretory process as the acini and indeed 

 seem analogous to the convoluted tubule in the kidney. The simi- 

 larity in histology between the striated ducts of the salivary gland 

 and the tubules in the aglomerular kidney of Lophius (Smith, 

 195 1 ) is very striking indeed. Further it may well be that the 

 somewhat derogatory term "duct" which has been responsible for 

 the neglect from which the collecting ducts (of Bellini) have only 

 recently been rescued, has also been responsible for a general 

 underestimation of the functional importance of the salivary ducts. 



The literature on the histology of the salivary glands is very 

 voluminous and citations of original papers would be inappropriate 

 to our purpose in this chapter, which is to provide a morphological 

 basis on which a discussion of the physiology of the salivary glands 

 can rest. The following account is taken from the reviews of 

 Merkel (1883), Zimmerman (1927), Stormont (1932), Rawlinson 

 (1933, 1934, 1935) and Leeson (1959). 



In general the salivary glands are organized on a lobular-race- 

 mose plan with the lobules being practically independent units. 



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