Acid Phosphatase Activity in Secretory Granules of Pancreatic Beta Cells of Normal Rats

A cytochemical staining method for acid phosphatase combined with electron microscopy was applied to the islets of Langerhans of adult normal rats. In addition to dense bodies, some Golgi cisternae as well as a varying number of secretory granules of β cells were found to contain acid phosphatase. In view of the paucity of the knowledge concerning the role of acid phosphatase, the possible functional significance of its presence in the secretory granules of pancreatic β cells cannot be denned at the present time.