Beta-Adrenoceptor Control of Peroxidase Synthesis in Nasal Glands

Abstract

Endogenous peroxidase activity was observed in the cisternae of the rough-surfaced endoplasmic reticulum (r-ER), including the nuclear envelope, Golgi complex, and secretory granules of the cat's nasal glands. A single injection of propranolol resulted in a decrease of peroxidase-positive secretory granules, an increase of electron-lucent granules, and no change in the level of peroxidase activity in the r-ER and Golgi complex at either 5 or 9 hours after the injection. Continuous administration of propranolol over 7 hours led to the disappearance of peroxidase activity from the r-ER and secretory granules. These data would indicate that propranolol inhibits only the synthesis of peroxidase. Twenty minutes after a single injection of isoproterenol, the rate at which the granule content containing the peroxidase reaction product was discharged into the acinar lumen increased sharply. However, 60 minutes after the injection, the secretion rate of peroxidase-positive granules decreased. The same experiment then was repeated, but this time before the isoproterenol was injected, propranolol was administered to the cats. This time no change in peroxidase activity appeared in the acinar cells. It was concluded, therefore, that the stimulation of beta-receptors enhances the synthesis of peroxidase.