[Effect of the antifolic preparation, tomizin, that possesses antitumor activity, on thyroid gland function].

Experimental investigations and clinical observations on the use of alkylating antineoplastic agents demonstrated these to influence the thyroid function. It is worthwhile to assess the effect of the antimetabolite tomizine, displaying antineoplastic properties, on the function of this organ. Tests conducted on rats with sarcoma M-1 disclosed the maximally tolerated doses of tomizine to produce a marked inhibition of the thyroid function. The latter is attended by a reduced accumulation of introduced 131I in the iron. Structural changes in the thyroid occurring under the effect of tomizine are characterized by the lowering of the thyroid epithelium height, increased dimensions of the follicles and a diminished volume of the insular tissue. This also points to depression of the thyroid function. Disturbances in this organ taking place under the effect of a single introduction of tomizine may be reversible. Multiple administration of the drug produces persistent functional disorders in the organ.