[Quantity of DNA, sex chromatin bodies and nucleoli in the nuclei of the muscle cells of normal and hypertrophied human atria].

Nuclei of myocytes of normal and hypertrophied human heart atrium were studied on squash preparations. Judging by the sex chromatin body pattern, it is the polyploidization that is responsible for the increased DNA contents in these nuclei. The cytophotometric DNA measurements demonstrated the up to 93% occurrence of polyploid nuclei even in myocytes of normal atrium. Myocytes of hypertrophied atrium contained nuclei of higher ploidy degrees. The total area of nucleoli per nucleus was shown to be proportional to a degree of ploidy.