A Quantitative Cytochemical Study of the "Polyploid" Liver Nuclei of the Frog Genus Pseudacris

Abstract

Microdensitometric determinations revealed nuclei belonging to 3 or 4 DNA classes with a doubling of the DNA content from class to class in the livers of breeding specimens of the frog genus Pseudacris. Quantitative cytochemical studies of the nuclear protein Indicate that these nuclei behave exactly like polyploid nuclei of other frog species although the range of nuclear sizes within each class was smaller than in the genus Rana. These livers may therefore be regarded as polysomatic tissues even in the absence of chromosome analyses.