Kinetochore-staining of spermatid micronuclei: studies of mice treated with X-radiation or acrylamide.

The rodent spermatid micronucleus (MN) assay was used in conjunction with immunofluorescent techniques to distinguish kinetochores in MN following exposure of mice to X-radiation or acrylamide. After either treatment, modest increases in kinetochore-positive MN were observed. Spermatids which had been exposed during meiotic prophase to X-rays (400 cGy) had approximately 10-fold increases in MN compared to controls; up to 15% of the MN observed were kinetochore-positive. Following acrylamide treatment of meiotic prophase cells, there was a doubling of spermatid MN over baseline levels, approximately one-third of which were kinetochore-positive.