Effect of Thyroid Hormone on the Ploidy of Rat Liver Nuclei as Determined by Flow-Cytometry

Abstract

The ploidy distributions of rat liver nuclei isolated from normal and thyroidectomized rats were determined after conjugation with fluorochromes acridine orange and propidium iodide by rapid flow cytometry on the basis of their DNA content. Using this technique, we have confirmed the marked influence of thyroid status on the ploidy of rat liver nuclei as compared to euthyroid rats of the same age. No further development of tetraploid nuclei occurred from the time of thyroidectomy. However, administration of 1 mg T3/100 g BW to hypo-thyroid rats led within 6 days to ploidy patterns identical with those observed in euthyroid animals of the same age.