Alpha-adrenergic stimulation and radiosensitivity on the rat submaxillary gland.

The submaxillary glands were exposed to fractionated irradiation comparable to 50 Gy in clinical practice and a single fraction of 50 Gy. Half the number of rats were given cyclocytidine, an alpha-adrenergic agonist which depletes the serous cell granules before irradiation was embarked upon. Our results show that irradiation causes a significant, irreversible destruction of serous cells. With cyclocytidine pretreatment, the radiodamage was diminished and this drug is suggested to act as a radioprotector, depleting secretory heavy metal granules, and thus preventing radiodamage in the submaxillary salivary glands.