[Morphophysiologic changes in the thyroid gland following exposure to retabolyl]

Area of Science:

• Comparative physiology
• Endocrinology
• Toxicology

Background:

• The thyroid gland regulates metabolism and development.
• Hormonal stress can lead to significant physiological changes.
• Understanding species-specific responses to stressors is crucial.

Purpose of the Study:

• To investigate the morphofunctional effects of retabolil on the thyroid gland.
• To compare the thyroidal response to retabolil in tortoises and white rats.
• To elucidate the relationship between thyrocyte proliferation and destruction under stress.

Main Methods:

• Comparative study involving 25 tortoises (Testudo horsfieldi) and 30 white rats.
• Histomorphological analysis of thyroid gland tissues.
• Assessment of thyroid hormone secretory phases.

Main Results:

• Retabolil exposure activated all thyroid hormone secretory phases in both species.
• Thyroid gland hypofunction was the initial state observed in tortoises.
• White rats exhibited increased physiological wear and destruction of thyroid cells, shifting the thyrocyte proliferation-destruction balance.

Conclusions:

• Retabolil induces significant morphofunctional changes in the thyroid gland.
• Species-specific differences exist in thyroidal response to retabolil-induced stress.
• The balance between thyrocyte proliferation and destruction is disrupted, favoring destruction under stress.