Survival of mouse mammary gland transplants of normal, hyperplastic, and tumor tissues exposed to X-rays.
Mouse mammary tissues, including ducts, prelactating lobules, hyperplastic outgrowth lines, and tumors, were exposed to varying doses of X-rays and then transplanted to fat pads of nonirradiated BALB/c mice for study. Estimates of the dose of radiation that would allow survival of 50% of the transplants (SD50) were made with the use of probit analysis. Nearly all duct and lobule transplants survived doses of X-rays from 0 to 800 rad. The survival rate declined rapidly following doses above 800 rad, and the calculated SD50 was 1,020 and 1,260 rad for mammary ducts and lobules, respectively. The three hyperplastic outgrowth lines tested gave very different results. Hyperplastic line Z5C1 transplants had better than 90% survival at doses up to 1,200 rad and an SD50 between 1,200 and 1,600 rad. Hyperplastic line Z5D transplants had an SD50 of between 800 and 1,200 rad. Hyperplastic line D1 transplants had a better than 90% survival following doses of 0-600 rad and an SD50 between 600 and 800 rad. The survival of tumor transplants was 100% following doses of X-rays up to 1,200 rad; the SD50 was in excess of 1,600 rad. The mouse mammary transplantation system can be used to study the direct effect of X-rays on normal, premalignant, and malignant mammary tissues and provides a basis for the study of the radiobiology of mammary tissues.
D000818:Animals; D002460:Cell Line; D006965:Hyperplasia; D008297:Male; D008321:Mammary Glands, Animal / Q000473:pathology / Q000528:radiation effects* / Q000637:transplantation; D008325:Mammary Neoplasms, Experimental / Q000473:pathology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009368:Neoplasm Transplantation; D011829:Radiation Dosage; D013997:Time Factors; D014965:X-Rays