• 한국환경성돌연변이발암원학회지
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• 제22권4호
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• pp.266-273
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• 2002

The dose dependence of the severity of radiation-induced thymic lymphoma in C57BL/6J mice was studied. Mice were exposed to fractionated irradiation at the total doses of 4.0, 6.0 and 8.0 Gy (four irradiations at 8-day intervals) starting from 33 days after birth. Pathological and histological changes of each mouse were observed after periodical sacrifice at day 75, 100, 125, 150, 175, 200, 250, 300 after the first irradiation. The severity of cancers were classified into 4 stages by clinical signs with respect to the enlargement of the thymus, spleen, liver, the progression of the cancer in the thymus, and the metastasis to the spleen, liver, lung and the lymphatic nodes. Among the 490 mice observed, 146 mice had thymic lymphoma. A clear dose-effect relationship was observed as well as the dose-response relationship. Also, periodical observation showed that thymic lymphoma was first induced in mice sacrificed at day 100 (130days old), and metastasize in the order of spleen, lung, liver and then the lymphatic nodes. The results suggest that radiation may be involved not only as a tumor initiator but also as a tumor promoter, and a tumor progression-enhancing agent.

• 대한수의학회지
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• 제27권2호
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• pp.269-275
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• 1987

Radiation-induced life shortening, carcinogenesis and other pathological changes were investigated in NIH(GP) mice after $^{60}Co-{\gamma}$ ray irradiation(100~700rads). The results were summarized as follows: 1. There were little difference in body weights, hematological examination and other clinical findings between normal and irradiated groups. 2. Mean survival time of the mice after irradiation were decreased dose-dependently. 3. Main gross findings of the mice irradiated were appeared as enlargement of spleen, thymus and lymph nodes, tumorous nodules of lung and cyst of ovary. Especially, enlargement of thymus was promineort in high dose group. 4. Microscopically, there were various findings including myeloid leukemia, thymic lymphoma, lung adenoma, adenosquamous cell carcinoma of pancreas, pneumonia and other pathological changes. Especially thymic lymphoma was highly frequent in the 700 rads group.