Morphological changes of thymus and the thyroid gland after postnatal extirpation of pineal body.

Extirpation of the pineal body of newborn rats was followed by the disorganization of thymic structure, follicular transformation and proliferation, viz. malignant transformation of its epithelial and connective tissue elements. Increase of connective tissue was also observed in the thyroid gland. The follicular cells contained crystal-like bodies and vesicles, whereas in the parafollicular cells the endoplasmic reticulum was increased and light granules appeared.