A way of hypothyriosis formation by thyrostatic mercazolil intraperitoneal introduction during 30 days with gradual increase of a doze is offered in this work. Biochemical verification of the given model has shown that level T4 increases 2.5 times as much in comparison with control animals, and level TSH increases 5.5 times. The morphometric analysis of the thyroid gland has confirmed hypothyriostatic and hyperplastic action of mercazolil which was showed in reduction of volumes of follicles, absence of the colloid, increase in follicles number by a fragmentation of greater follicles with perifollicularis capillaries and by proliferation of thyrocytes, increase in the volume of organ’s parenchyma and thyrocytes’ nuclei, and decrease in volume of the thyroid epithelium of one follicle.
