Summary: Effects of Thyroxine of axonal Regeneration in Tadpoles
Introduction: The experiment aims at determining the differences in binocular vision between a hormone-injected eye and a normal eye. Thyroxine hormone is believed to affect vision through its actions on the chiasm. When PTU-treated tadpoles’ eyes were injected with thyroxine hormone, there was a characteristic asymmetric growth of chiasm axons.
Methodology: tadpoles were used to determine the impacts of hormones on retinal axons proliferation in the ventral and dorsal ciliary region. To achieve this, the marginal zone tissues were transplanted, and the eyes of the cases injected with thyroxine. The transplants were labeled with PTU-treated tadpoles. The tadpoles that were reared with deep optic tract had additional axons added. The chiasma cells were lipoinfected with thyroxine, and only the tadpoles that expressed a surge in chiasma axon cells were counted in the study. The numbers of axons observed in the contralateral and ipsilateral brain were found in the absence and presence of the thyroxine hormone.
Results: There was no significant ventrotemporal growth of axons in the metamorphosing frogs. The non-retinal axons mostly crossed the chiasm midline projecting ipsilaterally to the retina. There were more axons at the contralateral and ipsilateral brain at stage 58-64, and the axons decreased as we moved towards stage 33/34. None of the transplant axon molecules crossed the midline of the chiasm. The study also found that there was isochromatic control of transplants at the ipsilateral section of the brain.
Conclusion: thyroxine hormone played a significant role in axonal development and regeneration in the chiasm retinal cells. Thyroid hormone alone was not sufficient in confirming the ipsilateral projection of axons at the retina while assessing for guidance cues in the brain.