The capacity of irradiated rabbit submandibular glands to concentrate 99mTcO4 pertechnetate.

The capacity of irradiated rabbit salivary glands to accumulate 99mTcO4 pertechnetate offers a means for functional evaluation of radiation injury. In 50 rabbits one side of the head was exposed to 15 Gy irradiation in a single dose. Measurements of isotope were made 4 and 10 months thereafter. The seromucous acini (80% of the intralobular tissue) were radiosensitive and showed a weight reduction. The striated ducts (8% of the intralobular tissue) were not radiosensitive and their weights did not change. The 99mTcO4 accumulation capacity of the glands was reduced by the irradiation, but by less than the total gland weight. Consequently the parenchymal concentration of 99mTcO4 was increased after irradiation. These findings suggest that 99mTcO4 is more concentrated in non-radiosensitive striated ducts than in radiosensitive seromucous acini.