Suppression of mitotic activity and synchronization of cell development in olfactory epithelium

Prolonged continuous application of hydroxyurea to frog olfactory epithelium suppresses mitotic activity in this tissue without side effects. After ZnSO4-induced coagulation necrosis of the olfactory epithelium, application of hydroxyurea prevents the usual epithelial regeneration. A method for obtaining frog olfactory epithelium with a developmentally synchronized neuronal population is introduced. The epithelium is first ablated by perfusion of the nasal cavity with ZnSO4. Then the epithelium is allowed to regenerate for 6 days, after which continuous introduction into the nasal cavity of hydroxyurea suppresses mitotic activity and thus the generation of new cells in the tissue. Cells formed during the 6 days prior to hydroxyurea treatment continue to develop. We found that the olfactory receptor cells are generated beginning on the 6th day after ablation, and so the epithelia contain a highly synchronized population of neurons all generated within about 24 h.