Abstract
The secretion of amines and proteins from glands has been investigated by many workers and it has been suggested that Ca2+ may be important in the secretory process (1-4), but it is uncertain whether Ca2+ actually participates in the secretory mechanism inside the cell.
The parotid glands are known to be innervated by the sympathetic and parasympathetic nervous systems and acetylcholine and noradrenaline are physiological stimuli that cause secretion of amylase from the gland (5, 6). Amylase is synthesized and stored mainly, in zymogen granules, in the parotid gland (7-10). Ultramicroscopically, zymogen granules are dense, round, osmiophilic bodies of about 1μ diameter, enclosed in a limiting membrane. They are easily isolated from the parotid gland by cell fractionation (8), and are well known to be important in secretion of amylase.
We study the mechanism of secretion by the parotid glands and the role of Ca2+ in the secretion process, especially in the release of amylase from zymogen granules. A preliminary note on some of this work has already appeared (11).
