Ploidy of micronucleated thyrocytes induced by methylnitrosourea injection.
Ploidy of thyroid parenchyma was studied in adult rats in the control and on day 9 after hemithyroidectomy; operated animals received 3 injections of N-nitroso-N-methylurea. The population of follicular thyrocytes is mainly diploid; total count of polyploid cells increased from 4.4% in the control to 8.5% in experimental rats. All thyrocytes containing micronuclei were tetraploid. No diploid micronucleated elements were detected. This suggests that genetically damaged thyrocytes divide by the mechanism of acytokinetic (polyploidizing) mitosis.
Pavlov
A V
AV
Department of Histology, Cytology, and Embryology, Yaroslavl State Medical Academy. pavlov@hist.yma.ac.ru
Gansburgskii
A N
AN
Gansburgskii
M A
MA
D000477:Alkylating Agents / Q000494:pharmacology; D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D004171:Diploidy; D008297:Male; D008770:Methylnitrosourea / Q000494:pharmacology*; D008938:Mitosis; D011003:Ploidies; D051381:Rats; D017208:Rats, Wistar; D013961:Thyroid Gland / Q000166:cytology* / Q000473:pathology*; D013965:Thyroidectomy
D000477:Alkylating Agents; D008770:Methylnitrosourea