A cytochemical study of mature mouse spermatozoa after C-banding treatment

Heterochromatin in mature mouse spermatozoa has been investigated by using C-banding treatment followed by either i) Giemsa staining, ii) staining with DAPI, a fluorochrome specific for AT rich DNA and iii) by using quantitative DNA measurements [Acriflavine-Feulgen, DAPI and Ethidium Bromide (EB)]. We have shown that a fraction of the mature sperm chromatin is affected by C-banding treatment. The sperm chromatin treated with Ba(OH)2 and stained with EB doubled fluorescence emission values found in untreated control preparations. This experimental result clearly shows that the use of intercalating fluorochromes, such as EB, is unsuitable for quantitative evaluation of highly condensed DNAs.