The Frequency of Appearance of the Metaphase Cells from the Primary Tissues of Rat Fetus

Abstract

The materials generally used in most chromosomal studies except for a particular purp ose are the cultured cells of animal or plant tissues. For the purpose of the studies of the chromosomal aberrations possibly obtainable by the administration of teratogens to the early embryo, the examination of chromosomes from the primary tissues of embryo is the most desirable, since it seems not to be able to rule out completely the possibilities of some disturbing effects by culture conditions (Bloom et aI, 1970) and/or culture media per se. Another reason why the primary tissue should be used is to examine the immediate effects of the teratogens upon the embryonic chromosomes within relatively short period of time, 2 to 5 days after administration of teratogens. However, it was impossible, if any, to find out the reports regarding the chromosomal studies, particularly the frequency of appearance of metaphase cells from the primary tissue of rat fetus. The intention of the present work is to develop a simple procedure of smear preparations from the chemical-free primary tissues of early rat fetus and to standardize the conditions by which an appropriate number of metaphase cells enough to analyze the cromosomal aberrations could be revealed