title: Seasonal variations of rat thyroid C cell population.
abstract: With the aid of argyrophilic and metachromatic reactions male rats' thyroid C cells were investigated in spring and autumn. Autumn C cells were found to be more swollen and richer in granules and showed a more pronounced metachromasia and argyrophilia than spring C cells. The area occupied by C cells in the central part of the thyroid lobe was large in autumn and reduced in spring. A study into the proportions of C cell: follicular cell: colloid: stroma indicated a significantly higher number of C cells in autumn than in spring.
mesh_terms: D000818:Animals; D003594:Cytoplasmic Granules / Q000648:ultrastructure; D051381:Rats / Q000033:anatomy & histology*; D012621:Seasons; D013194:Staining and Labeling; D013961:Thyroid Gland / Q000166:cytology*; D014617:Vacuoles / Q000648:ultrastructure