The influence of irradiation with 60Co-gamma ray on rabbit's submandibular gland

Fractionated irradiation of 7000 rads with 60Co-γ ray was given to the submandibular glands of rabbits for continuous 2 days. After exposure, morphological changes were examined by sialography and angiography, functional changes were examined with sup(99m)TcO4- and 131I-albumin, and pathohistological changes and changes of secreted particles were totally studied for 56 days. Until the 7th day after the irradiation, the duct system was dilated, snake-like flow of the vascular system was markedly observed, and inflammatory changes were found. Until the 14th day, split of the duct system, decrease of the number of the vascular system and mild inflammatory changes were continuously observed. After the 28th day, the findings were almost same as those of healthy control group. The examination with simultaneous administration of sup(99m)TcO4- and 131I-albumin revealed that the function of the glands and the blood flow volume increased at the 1st day after the exposure, and that the function of the glands continued to be enhanced. However, poor change was found in both from the 7th day and the function was almost same as that of the control group after the 14th day. Although inflamatory finding was slightly found until the 7th day, the finding was almost same as that of the control group after the 14th day. Although the number of the particles rapidly dropped after the exposure, it gradually recovered from the 7th day, and the finding was almost same as that of the control group after the 28th day. Total comparison of the above findings revealed that both functional and morphological changes in the submandibular glands appeared in early period after the exposure, but that the changes recovered relatively earlier in the functional aspect. (Kumagai, S.)