Development on thiocyanate peroxidase in salivary glands in the perinatal period of mice

Abstract

Antibacterial action of human saliva has beenone of the central subjects in oral biology and numerous studies have been reported. Among the antibacterial factors present in human saliva, the salivary peroxidase has received the most extensive studies. The salivary peroxidase antibacterial system consists of three integral components, that is, salivary peroxidase, hydrogen peroxide and thiocyanate. This antibacterial enzyme is referred to thiocyanate peroxidase. Thiocyanate peroxidase was also observed in the tissue extracts from the salivary glands of the rat, the guinea pig and the cattle.Although the mode of action of the thiocyanate peroxidase has now been largely clarified, the origin of this enzyme remains obscure.The purpose of this experiment is to study the origin of this enzyme in the salivary glands of developing mouse with tissue culture technic.The experimental results are as follows: (1) The activity of thiocyanate peroxidase was detectable at 17 th day in utero in the sub maxillary gland of the mouse, and at the 2 nd day after birth in the parotid gland. There was a progressive increase in the enzyme activity throughout the various stages of perinatal development. This enzyme could not be detected in the sublingual gland of either pre-or postnatal mice. (2) Embryonic submaxillary, sublingual and parotid glands of mice were successfully cultivated using Rose's chamber, and the differentiation and proliferation of glandular tissues were observed for approximately 5 days. The peroxidase in cultivated tissue could be stained by the method of Straus with benzidine. According to the acinar differentiation, the positively stained product in blue which presume secretory granules was developed in secretory cells of the submaxillary gland and parotid gland on the 3rd day after cultivation. However, no positive staining reaction was obtained in the sublingual gland. The possible relation between the positively stained product and the thiocyanate peroxidase is discussed. (3) These findings strongly suggests that the thiocyanate peroxidase develops in the acinar cells of the submaxillary and parotid glands during the perinatal period of the mouse.