Factors affecting the sensitivity of rabbit lymphoid and bone marrow cells to Streptonigrin-induced chromosome aberrations.
In previous cytogenetic studies of rabbits injected with the clastogen, streptonigrin (SN), we observed a higher incidence of chromosome aberrations in lymph node cells than in marrow cells recovered 6 h after treatment. In this study we examined several factors that may be responsible for this difference in the incidence of lesions. Results from SN pulse-treated lymphoid and marrow cultures demonstrated that the responses were different in vitro also. In addition, at higher doses of SN, lymphoid cells displayed a greater sensitivity to the drug when treated during DNA synthesis; marrow cells showed no differences in sensitivity throughout the cell cycle. Analysis of the percentage of lymph node and marrow metaphases labeled following 2, 4, or 6 h of culture in the presence of tritiated thymidine indicated that G2 was less than 2 h in lymph node cells and approximately 4 hr in marrow cells. From these data we conclude that the difference in the incidence of lesions 6 hr after an in vivo SN exposure. However, our data also indicate that lymph node cells are innately more sensitive to the induction of lesions than are marrow cells.
D000818:Animals; D001854:Bone Marrow Cells; D002869:Chromosome Aberrations; D004247:DNA / Q000096:biosynthesis; D007399:Interphase; D008198:Lymph Nodes / Q000166:cytology; D008214:Lymphocytes / Q000187:drug effects / Q000648:ultrastructure*; D011817:Rabbits; D013308:Streptonigrin / Q000494:pharmacology*
D013308:Streptonigrin; D004247:DNA