Effect of the gravity change on thyroid tissue of WT animals.

<p>a) Morphology analysis of parafollicular thyroid cells. “vivarium 1”: mice maintained in vivarium cages (control for experiment in hypogravity); “hypogravity”: experimental mouse in space; “vivarium 2”: control for experiment in hypergravity; “hypergravity”: experimental mice in 2×g centrifuge. Hematoxylin-eosin staining, 40× magnification, 1 µm scale bar. F = follicle. b) Ratio between the number of follicular cells of three follicles delimiting a parafollicular area and the number of cells C in this area. The values are expressed as mean ± SD of three independent fields observed in duplicate (7 and 13 sections). (Significance, **P<0.001 space versus vivarium 1 and 2 g versus vivarium 2).