[Modifying effect of methylcobalamin in organ cultures of the mouse kidney when administered transplacentally in combination with N-nitrosoethylurea].

The influence of methylcobalamin (MeCbl) on transplacental effect of N-nitrosoethylurea (NEU) was studied in organ cultures of embryonic tissue of DBA/2 mice by the histoautoradiography (3H TdR). A combined transplacental treatment of pregnant mice with MeCbl and NEU produced a 3.3-fold increase in the frequency of focal hyperplastic growth of epithelium as compared to the effect of NEU alone. Under such conditions the modifying effect of methylcobalamin, coenzyme of methionine synthetase, was probably due to an increase in the proliferative activity of epithelial cells.