Comparative Histology of Parotid Glands in Mammals

Abstract

Malabika Debi1 , Arup Jyoti Sarma2

BACKGROUND Parotid glands are one of the major salivary glands of mammals, responsible for production of the saliva. We wanted to do an interspecies comparison of the histology of mammalian parotid glands. METHODS Three (3) species were included in the study: human, pig and goat. Specimens were collected from study subjects in the adult age range. Acinar as well as ductal elements were observed under both low- and high-power objectives after staining the sections with routine haematoxylin and eosin stains. RESULTS Serous acini lined by serous cells were seen to occur in the parotid glands of all the three mammalian species. In human and pig, these cells were predominantly serous; whereas in goat, mucous cells were also noted amongst serous cells. In our study, striated ducts were found to be widely dispersed throughout the parotid glands of all the three mammals, constituting the largest portion of the duct system of mammalian parotid salivary glands. CONCLUSIONS Parotid glands are major salivary glands occurring bilaterally which exhibit considerable structural diversity among different species. A better knowledge of the cytoarchitecture and distribution of various elements in the different portions of the salivary excretory system is not only important from a biological point of view, but also because of their important role in the histogenesis of certain types of salivary gland tumours.

image