[Crystalline inclusions of the mouse thyroid. Effect of chronic treatment with lithium gluconate]

Intracytoplasmic crystalline bodies of various sizes are found in thyroid cells of 10-month-old mice and in younger animals under chronic lithium treatment. They are frequently surrounded by small microvesicles and dense bodies or enclosed in larger vesicles having a dense content. The crystalline skeleton is a network of protein fibers assembled in a characteristic axis with a periodicity of 8 nm. A deficiency of thyroid cell metabolism related to aging or lithium gluconate treatment would lead to an accumulation of substances of a crystalline pattern.