Cytophotometry of feulgen-naphtol yellow S stained liver cells--a computerized method for the calculation of nuclear protein.

A computerized method was developed to calculate the nuclear protein content of Feulgen-Naphtol Yellow S stained liver cells from cytophotometric data. After two consecutive scannings at 570 nm (DNA) and 435 nm (protein), the nuclear localization and shape are defined and nuclear protein is calculated by a method which corrects for the nuclear-cytoplasmic overlap at the nuclear periphery. The results obtained by the procedure are highly reproducible and are in accordance with the results of biochemical determinations of nuclear and total cell protein reported by others.