Cell proliferation and migration in tectum opticum in the Xenopus laevis tadpoles and adults in the norm and upon brain trauma. II. Cell proliferation and differentiation in tectum opticum in adults

The proliferation and directions of cell differentiation in tectum opticum were studied in young frogs under the conditions of normal development and upon brain trauma by means of 3H-thymidine autoradiography. The same types of cells were shown to be capable of proliferation in both the cases: cells of the ventricle zone and glioblasts (gliocytes) in all other tectum layers. A study of directions of the tectum proliferating cells' differentation in the frogs has shown that the proliferating cells differentiate mainly in the ependyme tanicytes in the ventricle layer 1 and gliocytesin the other tectum layers. The trauma did not change the direction of proliferating cells' differentiation towards the formation of neurons. The complete regeneration is observed in the tectum layer 1 only.