Effects of autonomic agents on the secretion of glycoproteins from the secretory cells of the major salivary glands in rats.

The characteristics of the glycoproteins contained in the secretory segments of the three major salivary glands of adult male rats and the secretion of these various glycoproteins in response to autonomic agents were examined by micro-disc electrophoresis. Characterization of the glycoproteins showed that the acinar segments from the three major salivary glands and the segments of the convoluted granular tubules from the submandibular gland each contain characteristic species of glycoproteins. The glycoproteins characteristic of the acinus of the submandibular gland were secreted into saliva in response to carbachol or dobutamine, those characteristic of the parotid gland by carbachol, methoxamine, or dobutamine, and those of the sublingual gland by carbachol, whereas glycoproteins characteristic of the convoluted granular tubules of the submandibular gland were only elicited by methoxamine. The secretory response of carbachol, methoxamine and dobutamine, respectively, were almost completely reduced by pretreatment with atropine, prazosin and metoprolol. The relative proportions of glycoproteins secreted into the oral cavity from secretory cells of the three major glands varied significantly with the nature of the stimulant.