Identification of Teratogens in Cell Culture. Ii. Laboratory Values of Rat Embryo Midbrain Studied by Micromass Test with Penicillin G and 5-fluorouracil

One of the model system that is included in the battery of tests for in vitro embryotoxicity studies is Micromass test. However, this test is based on the rat embryo limb bud cell culture and disregards other tissues. The aim of this work was to optimize culture condition and to check the influence of initial cell density and spot volume plated on the evaluation of embryotoxicity. Two model compounds (penicillin G at the concentration of 500 μg/ml and 5fluorouracil at 7 concentrations ranged from 15.625 to 1000 ng/ml)) were used. It was confirmed in control cultures that viability was directly related to the number of cells plated, however, it had no significant influence on the evaluation of the compounds. In nine runs IC50 values of 5-FU were similar for proliferation and differentiation and ranged from 148 to 257 ng/ml. In PEN-G cultures the viability ranged from 80 to 95% of controls.